Fossil Birds From 

Manix Lake 

California

By HILDEGARDE HOWARD

A SHORTER CONTRIBUTION TO GENERAL GEOLOGY

GEOLOGICAL SURVEY PROFESSIONAL PAPER 264-J

Descriptions of late Pleistocene bira 

remains, including a new species 

of flamingo

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1955
UNITED STATES DEPARTMENT OF THE INTERIOR 

Douglas McKay, Secretary

GEOLOGICAL SURVEY 

W. E. Wrather, Director

For sale by the Superintendent of Documents, U. S. Government Printing Office 

Washington 25, D. C. - Price 40 cents (paper cover)
CONTENTS

Page

Abstract--__-_-----___-__-__-_--___________________ 199

Introduction _______________________________________ 199

Description of specimens_____________________________ 201

Aechmophorus occidentalis (Lawrence)_____________ 201

Pelecanus erythrorhynchos Gmelin_________________ 202

Phalacrocorax auritus (Lesson) ?_________________ 202

Ciconia maltha Miller_____.______________________ 202

Phoenicopterus copei Shufeldt?_.__________________ 202

Phoenicopterus minutus Howard, new species_ ______ 202

Page 

Description of specimens—Continued

Branta canadensis (Linnaeus)_--____--_____-_-___- 203

Nyroca valisineria (Wilson) ?____________________- 203

Erismatura jamaicensis (Gmelin)__________________ 204

Aquila chrysaetos (Linnaeus)_____________________ 204

(?rws?_______________-_-______-____-_--__- 204

Family Phalaropodidae__________________________ 204

Summary and conclusions__________________________ 204

Literature cited___________________________________ 205

ILLUSTRATIONS

PLATE 50. Phoenicopterus minutus Howard, new species._________________________________________________ Following 206

FIGURE 42. Map of the Manix Lake fossil deposits____-___________________--_________-__--__---__--------_-------- 200

in

A SHORTER CONTRIBUTION TO GENERAL GEOLOGY

FOSSIL BIRDS FROM MANIX LAKE, CALIFORNIA

By HlLDEGARDE HOWARD

ABSTRACT

Sixty fossil bird bones have been recovered from the Manix 

Lake deposits in the Mohave Desert. These can be assigned to 

12 species of which 3 are extinct. One of the extinct species is 

a small flamingo, new to science, here described as Phoenicopterus 

minutus Howard.

Ecologically, the avifauna is in keeping with the lacustrine 

origin of the Manix deposits, and compares favorably with that 

of the upper Pleistocene bedb of Fossil Lake, Oregon, though of 

less varied content. The species, with the exception of the 

newly described form, are all known from upper Pleistocene 

deposits on the west coast.

INTRODUCTION

Through the courtesy of D. Foster Hewett, of the 

United States Geological Survey, a collection of fossil 

bird bones from the Manix Lake beds has been deposited at the Los Angeles County Museum for study 

and recording. The bones were collected as a part of 

the Survey's project of mapping the entire Mohave 

Desert area, studying its structural problems, and 

determining the distribution of saline deposits. This 

work was begun in 1947 under the direction of Mr. 

Hewett. Several collectors have aided in this undertaking, but most of the bird remains were collected in 

1952 by Herbert Winters; two of the specimens were 

contributed by D wight Taylor. To the Geological 

Survey specimens have been added two others collected in October 1953 by Theodore Downs and Leonard 

Bessom of the Los Angeles County Museum.

The Manix basin is in San Bernardino County, Calif., 

about 30 miles east of Barstow. The fossiliferous 

localities lie in an area of some 200-300 square miles. 

The localities were first described by Buwalda (1914) 

who obtained a collection of mammal and bird bones 

and fresh-water mollusks. Six mammals, including 

Equus, were listed but not specifically defined. .

326648—55

The bird bones collected by Buwalda were described 

by Compton (1934) who recorded two species of water 

birds, Pelecanus erythrorhynchos and Aechmophorus 

occidentalis, based on four well-preserved bones.

In the course of the Geological Survey's more recent 

undertaking, both bird and mammal bones have been 

collected. The mammal bones are on deposit at the 

California Institute of Technology, and are being 

studied by Herbert Winters. 1 The Institute records 

the mammalian fossils under three locality numbers, 

540, 541, and 542. All the bird bones are from 540, 

which also bears the Los Angeles County Museum 

locality number 1093. At the time of excavation, 

collection numbers were assigned to each bone occurrence (see map, fig. 42). According to Winters (personal communication) those that yielded avian remains 

fall into four groups in point of lithology and vertical 

occurrence, as follows:

Unit * Depth Collection numbers

!_________ 1-16 feet....... T10 and Wl.

4_._______ 21-23 feet___._. W12, W21, W2?.

16._______ 81-85 feet-.-... W16, W17, W19, W29, TD316.

17_...____ 86-111 feet___._ W5, TD318?.

Unit 17 is underlain by a "bouldery conglomerate" in 

which no fossils were found in place. One bone was 

collected by the Los Angeles County Museum on the 

surface of the conglomerate (TD 318), and was possibly 

derived from Unit 17.

Sixty identifiable bird bones have been collected, 

representing twelve species. The distribution of the 

species is shown in the table below.

1 Winters, Herbert, The fauna of the Pleistocene Manix beds in the Mojave Desert, 

California. (Report in preparation.)

2 Unit numbers correspond to those listed by Winters (manuscript) with full 

lithologic descriptions. Individual collectors are indicated by letters preceding the 

numbers, as follows: T, Dwight Taylor; W, Herbert Winters; TD Theodore Downs.

199
200 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

5000 Feet

_I

FIGURE 42.—Map showing U. S. Geological Survey collecting sites at Manix Lake, San Bernardino County, Calif. Numbers underlined indicate localities that yielded avian 

remains. Los Angeles County Museum collecting sites that yielded avian remains were in the general vicinity of W24 (TD 316) and W25 (TD318).

T3, etc., Dwight W. Taylor collecting sites.

W6, etc., Herbert W. Winters collecting sites.

CIT 640-541-542, California Institute of Technology locality numbers. (CIT 540=L. A. Co. Mus. 1093.)
FOSSIL BIRDS FROM MANIX LAKE, CALIFORNIA 201

Species of birds from the Manix Lake deposits 

[Los Angeles County Museum locality 1093, California Institute of Technology locality 540]

Aechmophorus occidentalis (Lawrence)..-- __ _________ _

Pelecanus erythrorhynchos Gmelin __ ________ ____

Phalacrocorax auritus (Lesson) ?.______ ______

Ciconia maltha Miller.. __________ ___

Phoenicopterus copei Shufeldt?. _____ _ _____

Phoenicopterus minutus Howard, n. sp __ __ ______

Branta canadensis (Linnaeus)--- ____ _ _ ___

Nyroca valisineria (Wilson) ?___ _________ ______

Erismatura jamaicen&is (Gmelin) ____ ______ _ ___

Aquila chrysaetos (Linnaeus)---___-_ _ ___ ____

Grusl.... _____ _ _____ __ ______ ______ _ __

Family Phalaropodidae. ___ __ ______ __ _ _ ___ _

i

T10

X

Wl

V?

W2

v

4

W12

X

W21

X

W16

V?

v

Unit

W17

X

16

W19

X

X

X

W29

X

X?

TD316

X

W5

X?

17

TD318?

X

No 

data

X

X

X

X

X

DESCRIPTION OF SPECIMENS

Genus AECHMOPHORUS 

Aechmophorus occidentalis (Lawrence)

The bones of Western Grebe include complete tarsometatarsi, femora, nearly complete tibiotarsi, and 

fragments of several other skeletal elements of one 

individual (LACM 2457) from W21, and a separate 

coracoid (LACM 2465 from W19) and proximal end 

of tarsometatarsus (LACM 2458, with no field data). 

A complete humerus (LACM 2469 from W19) and 

fragments of vertebrae and tarsometatarsus (from Wl 

and W16 respectively) are tentatively identified.

A previous comparison (Howard, 1946, p. 148-151) 

between Recent grebe bones and those from Fossil 

Lake, Oregon, revealed certain differences between the 

living and the Pleistocene forms. Although measurements of the two series overlapped, the fossil grebe 

(assigned to A. occidentalis lucasi) tended to have 

longer legs, with tarsometatarsi relatively broader and 

deeper of shaft, but narrower proximally.

Measurements of the Manix Lake fossils are given 

in the table below. The humerus (from W19) is shorter 

than the minimum for either of the previously recorded 

series. It is not, however, small enough to be considered with Colymbus parvus, and the physical characters 

of the bone are similar to Aechmophorus rather than to 

Colymbus. Possibly a new species of Aechmophorus is 

represented, but it seems inadvisable to erect it on the 

basis of a small size difference of a single bone. In 

length, the leg bones from W21 (LACM 2457) fall in 

the zone of overlap of the Fossil Lake and Recent 

specimens, although all are equal to or greater than the 

average for A. o. lucasi. Except for breadth of proximal end, the proportions of the two complete tarsometatarsi suggest this chronocline. This is particularly true 

of the breadth of the intercotylar tubercle, which is 

considerably narrower with respect to the breadth of 

shaft than in the Recent Western Grebe. The same 

is true of the separate specimen of proximal end of 

tarsometatarsus (LACM 2458).

Measurements (in millimeters) and proportions of Western Grebe bones 

[Recent and Fossil Lake specimen data from Howard (1946, p. 148-150. Figures in parentheses are means.]

Length of tarsometatarsus- __ _ _____ __ _ _ __._ ______ ___ __ ______

Length of femur _ _ _ _ _______ _______ _ __ ___ ___ ____________

Proportions of tarsometatarsus relative to length (in percent) : 

Breadth, shaft. __ _ ____ ____ ______ _ ______ ____ __ _ _______

Breadth, intercotylar tubercle of tarsometatarsus, to breadth of shaft (perRecent

108-128 (116)

40-49 (44)

68-81 (74)

111-127 (119)

41-47 (44)

4.3-5.0 (4.6)

16.5-18.2 (17.3)

8.2-9.3 (8.7)

146-170 (154)

Fossil Lake

110-125 (119)

40-50 (46)

68-86 (77)

119-130 (125)

42-50 (46)

4.6-5.6 (4.9)

15.4-18.1 (16.9)

8.6-9.8 (9.2)

123-162 (140)

Manix Lake

106.5

40

79

125

46

5.5

17.3

9.2

123-125
202 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

Genus PEIECANUS 

Pelecanus erythrorhynchos Gmelin

An anterior end of left coracoid and distal end of 

right femur agree with bones of large individuals of 

Recent White Pelican. A fragment of proximal end of 

a very large radius is tentatively assigned to this species.

Genus PHAIACROCORAX 

Phalacrocorax auritus (Lesson)?

A distal half of left and proximal fragment of right 

ulna are tentatively assigned to this cormorant. The 

bones are similar to those of P. auritus and P. penicillatus. These species are difficult to distinguish on the 

basis of the ulna. The small size of the specimens 

precludes the possibility of identification as the large 

extinct P. macropus described from Fossil Lake, Oreg.

Genus CICONIA 

Ciconia maltha Miller

One distal end of right humerus (LACM 2463) is 

indistinguishable from specimens of humerus of this 

stork found at Rancho La Brea.

Genus PHOENICOPTERUS 

Phoenicopterus copei Shufeldt?

Two species of flamingo are clearly represented, one 

large and the other very small. The large one is 

represented by a single tarsometatarsus of a young bird 

(LACM 2448). The well ossified tarsal section is not 

fused to the spongy proximal part of the metartarsals, 

but is preserved separately. The distal end seems to 

be completely ossified, but owing to fracture, cannot be 

precisely restored. When the tarsal section is held in 

place, the complete element is approximately 328 mm 

long. This measurement falls within the size range of 

both Phoenicopterus ruber and P. antiguorum. It 

probably does not, however, represent the actual 

length which this element would have attained in 

maturity. The breadth across the proximal articular 

surface exceeds the maximum of available specimens of 

both P. ruber and P. antiguorum (see table below).

The intercotylar tubercle of the proximal end is relatively high and pointed as in P. ruber, but is broader 

both in actual measurement and in proportion to the 

breadth of the proximal end.

The proximal end of the tarsometatarsus of Phoenicopterus copei from the Pleistocene of Fossil Lake, 

Oreg., is not known, but its size is indicated by the 

dimensions of the distal end of tibiotarsus which 

articulates with it. The distal end of tibiotarsus in 

P. copei is broader than in P. ruber or P. antiguorum: 

the width between the condyles is broad, suggesting 

that the intercotylar tubercle of the tarsometatarsus, 

which fits into this space when the bones are articulated, was also broad (Howard, 1946, p. 158), as noted 

above for the Manix Lake specimen. Therefore, a 

tentative assignment of the Manix Lake tarsometatarsus to this known fossil species seems reasonable.

Phoenicopterus minutus Howard, n. sp.

A small flamingo is represented by a nearly complete 

tibiotarsus with associated proximal portion of tarsometatarsus and an additional proximal fragment of 

tarsometatarsus. These leg bones show that the bird 

not only was smaller than any known flamingo but 

also differed in other respects.

Type.—Nearly complete right tibiotarsus and proximal % of tarsometatarsus found together and undoubtedly representing the same individual (articulation exact). Los Angeles County Museum number 

2445. Collected by Herbert Winters.

Locality.—Approximately 2% miles ESE of town of 

Manix, San Bernardino County, California; depth 

81-85 feet from surface; Los Angeles County Museum 

locality 1093, equivalent to California Institute of 

Technology locality 540; collection number W19.

Referred material.—Proximal end of left tarsometatarsus, Los Angeles County Museum number 2473, 

collected by Theodore Downs and Leonard Bessom. 

Collection number TD318, Los Angeles County Museum locality 1093.

Diagnosis.—Very small flamingo; approximately 13 

mm shorter in tibiotarsus than smallest available

Measurements of (in millimeters) Phoenicopterus tarsometatarsi

Breadth, proximal articular surf ace _

Breadth, intercotylar tubercle. ___.

Height, intercotylar tuber ale.. _ _.

Ratio, height to breadth of tubercle 

Ratio, breadth tubercle to breadth p

(in percent)--. __. .____-___ - _____

Manix 

Lake 

specimen 

LACM 

2448

19.0 

12.0 

6.8 

56.6 

63.2

P. antiquorum

18.1-18.7 

11.7-12.3 

5.2-6.2 

43.5-50.4 

64.6-65.7

P. ruber

15.5-17.6 

9.1-11.0 

5.4r-5.9 

53.6-61.5 

55.5-62.5

P. chilensis

16.3-16.8 

9.8-10.7 

4.8-5.3 

49.0-49.5 

60.1-63.7
FOSSIL BIRDS FROM MANIX LAKE, CALIFORNIA 203

P. chilensis; 0.2 mm narrower and 1.0 mm less in 

depth of distal end than in P. stocki. Breadth between 

distal condyles of tibiotarsus narrow; intercotylar 

tubercle of tarsometatarsus narrow and high.

Discussion.—Through the courtesy of the California 

Institute of Technology, the type tibiotarsus of P. 

stocki (Miller, 1944), a very small form from the

Pliocene of Mexico, was made available for comparison. 

P. minutus is not only smaller than P. stocki, but 

other distinctions may be noted as follows: 1, Relatively, as well as actually less deep through distal end; 

P. stocki resembles P. ruber in this proportion, whereas 

P. minutus agrees more closely with P. antiquorum 

(see table below). 2, The position of the notch on

Measurements of Phoenicopterus bones

[Measurements in millimeters, ratios in percent. Asterisks indicate measurements of type specimen.]

Tibiotarsus : 

Length. __ ____ __ _____ ___ ___ _ ______ _ ___

Breadth, distal end- __________ __ __ __ _ _____ _

Breadth between distal condyles._ _________

Distance from anterior end of internal condyle to notch

Ratio, depth to breadth distal end ___ ______ __ ._

Ratio, breadth between condyles to breadth distal end__ 

Ratio, distance to notch relative to depth distal end___

Tarsometatarsus : 

Breadth, proximal articular facet. __ ____

Breadth, intercotylar tubercle ____ _______ __

Height, intercotylar tubercle. _ _ ______ _____

Ratio, breadth intercotylar tubercle to breadth proxiRatio, height to breadth intercotylar tubercle . _ _ _

P. minutus

222.2

12.7

15.0

8.1

9.3

118

63.6 

62.0

13.8-14.6*

8.2-8.4*

5.0-5.2*

57.5*-59.4

60.9-61.9*

P. stocki

12.9

16.0

8.7

8.2

124

67.4 

51.2

P. chilensis

235.0-297.2

14.2-15.4

15.7-17.5

9.7-11.2

9.3-10.1

110-114

68.3-73.2 

56.6-59.3

16.3-16.8

9.8-10.7

4.8-5.3

60.1-63.7

49.0-49.5

P. ruber

285.6-304.3

13.3-15.5

17.5-19.4

9.7-11.3

10.4-11.7

123-131

71.4-73.0 

59.2-62.9

15.5-17.6

9.1-11.0

5.4-5.9

55.5-62.5

53.6-61.5

P. antiquorum

300.5-363.7

16.5-16.6

17.8-19.6

11.6-11.7

11.1-11.3

107-119

70.4-70.5 

56.5-63.5

18.1-18.7

11.7-12.3

5.2-6.2

64.6-65.7

43.5-50.4

the distal border of the internal condyle is well behind 

the center of the condyle in P. minutus, as in P. ruber; 

in P. stocki this notch is almost exactly in the center. 

3, The anterior intercondylar area is 0.6 mm narrower 

in P. minutus than in P. stocki, though both fossil, 

flamingos are relatively narrower in this area than 

any of the living forms. No comparison of tarsometatarsus can be made with P. stocki. Compared 

with Recent flamingos, the tarsometatarsus of P. 

minutus has a very narrow, high intercotylar tubercle. 

In the type specimen the height relative to the breadth 

of this tubercle is greater even than in P. ruber.

Two scapulae and a fragment of coracoid of flamingo 

are probably assignable to P. minutus. The scapulae 

are of about equal size and do not seem to differ 

markedly in this respect from modern species of 

Phoenicopterus. The slight variations in contour that 

are normal within a species in the genus Phoenicopterus 

make difficult the taking of comparative measurements 

even among Recent specimens. The two fossils differ 

in their contours; in one (LACM 2446) the glenoid 

area rises gradually from the shaft, whereas in the 

other (LACM 2474) the area juts out abruptly; variation within the modern species includes the condition 

noted in LACM 2446 but not that of LACM 2474. 

The fossil scapulae resemble each other and differ 

from all modern forms at hand in having a smaller, 

more inflated glenoid facet. Recent specimens indicate

326648—55——2

that this latter character is more significant than the 

contour noted above.

The coracoid seems to belong to a bird larger than 

that represented by the scapulae. It is, however, too 

fragmentary to base any conclusions thereon. The 

coracoid and both scapulae were found at the same 

general level as the type of P. minutus. Scapula 

LACM 2446 is similar in coloration and preservation 

to the type bones; scapula LACM 2474 and the 

coracoid are considerably whiter and smoother of 

texture.

Genus BRANTA

Branta canadensis (Linnaeus)

Proximal and distal ends of right femur are assignable to this species. The head of the femur seems 

to be somewhat smaller than the specimens of Canada 

Goose (B. canadensis canadensis) at hand, but the 

fossil bone is considerably worn in this area. Otherwise the bone equals in size this large race of Branta 

canadensis.

Genus NYROGA

Nyroca valisineria (Wilson) ?

A distal end of left humerus and a nearly complete 

scapula represent the genus Nyroca. As N. valisineria 

and N. marila are not readily distinguished, the 

assignment to valisineria is tentative.
204 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

Genus ERISMATURA 

Erismatura jamaicensis (Gmelin)

An anterior end of sternum is assignable to the 

Ruddy Duck.

Genus AQUILA

Aquila chrysaetos (Linnaeus)

One incomplete right distal end of tibiotarsus is 

very poorly preserved, yet distinguishable as Golden 

Eagle. Detailed field data are lacking on this specimen, 

but the adhering matrix appears to be that of Unit 16.

Genus GRITS?

A badly fragmented distal end of humerus should, 

perhaps, not be even tentatively assigned. Breakage 

has occurred in most of the diagnostic areas. Merely 

by way of recording it for size and general characters, 

the specimen may be said to suggest the Lesser Sandhill 

Crane, Grus canadensis canadensis.

Family PHALAROPODIDAE

An incomplete tibiotarsus closely resembles bones of 

Phalaropus fulicarius, but could possibly represent 

one of the other living genera and species of phalarope.

SUMMARY AND CONCLUSIONS

Twelve species of birds are represented in the Manix 

Lake material at hand. Two of these had previously 

been recorded from the area (Compton, 1934). Three 

extinct species are listed, one of which is described 

as new.

Although this avifauna is small, the presence of two 

species of flamingos immediately marks it as significant. 

Only one other record of this group is known in California, an extinct genus (not a true flamingo) recorded 

by Miller (1950 and 1952) from the Barstow, upper 

Miocene. The Manix occurrence, however, is the first 

record of the genus Phoenicopterus for the state. The 

ever-increasing fossil record of flamingoid forms points 

more and more clearly to the past importance of this 

group of water birds; following is a list of the species 

now known from fossil deposits in North America:

Megapaloelodus connectens A.

Miller. 

Phoenicopterus floridanus

Brodkorb

Phoenicopterus stocki L. Miller 

Phoenicopterus copei Shufeldt

Phoenicopterus minutus Howard

Lower Miocene, South Dakota 

Upper Miocene, California 

Middle Pliocene, Florida

Pliocene, Chihuahua, Mexico 

Upper Pleistocene, Oregon 

Pleistocene, California ? 

Pleistocene, California

The Manix Lake avifauna parallels that recorded 

from Fossil Lake, Oreg. (Howard, 1946). The grebes,

pelicans, cormorants, flamingos, ducks and geese from 

both areas reflect the lacustrine nature of the deposits. 

With the exception of the grouse at Fossil Lake, which 

would not be expected so far south, many of the other 

species that occur at the northern locality may in time 

be found at Manix Lake. Two birds are listed for the 

Manix deposits that are not recorded from Fossil Lake. 

One (the fragment listed as Grus?} is too fragmentary 

to be accorded any importance; the other is the new 

species of small flamingo. Like the grouse of the 

northern locality, this species may have had a limited 

distribution, although the possibility of an age difference between the two deposits cannot be overlooked.

The age of the Manix was originally (Buwalda, 

1914, p. 451) given as Pleistocene, without specification 

of the stage represented. Later, Compton (1934, 

p. 167), influenced by the presence of small horse bones 

which he believed to be of Pliocene age, concluded that 

the beds were early Pleistocene, or even late Pliocene 

in age. However, the avian species he recorded are 

both still extant.

Most of the avian fossils here reviewed suggest the 

late Pleistocene. However, in view of the fact that 

the bones were collected at different levels, a careful 

study was made to determine the possibility of representation of more than one geologic age. This study 

proved inconclusive. The cormorant and grebe from 

the uppermost beds can be only tentatively assigned, 

but appear to be similar to living forms. From the 

21-23 foot level, the large flamingo is an extinct species, 

Apparently the same as that from the late Pleistocene 

of Fossil Lake; the grebe belongs to a living species, 

though possibly an extinct, chronocline of that species 

known in the late Pleistocene; and the bone tentatively 

assigned to Grus is uncertain. From the 81-85 foot 

zone, the small flamingo and the stork are extinct, 

the stork being the same as that from the upper Pleistocene deposits of Rancho La Brea, the flamingo heretofore unknown; the grebe humerus is notably small, 

which fact may be of significance, but without further 

material is inconclusive evidence of difference from 

the grebe of the higher level. All other specimens 

apparently represent species that are still living.

Very little is known of lower or even middle Pleistocene birds in the United States. The few finds that 

have been recorded do not appear to differ markedly 

from those of the upper Pleistocene. Pliocene avifaunae, however, show a predominance of forms which 

are distinct from those now living. Contrasted with 

the upper Pleistocene deposits of Fossil Lake and 

Rancho La Brea, in which 25-30 percent of the avian 

species are extinct (Howard, 1946, p. 194), upper 

Pliocene avifaunae of Arizona, Idaho and Kansas have
FOSSIL BIRDS FROM MANIX LAKE, CALIFORNIA 205

from 60 to 66 percent extinct species (based on listings 

by Wetmore, 1924, 1933, and 1944, respectively), and 

the middle Pliocene avifauna of San Diego, California 

is entirely extinct (Howard, 1949, p. 198). With so 

few species represented from each level in the Manix 

deposits, and at least three species present for which 

the level is not known, no accurate percentage of 

extinct to living species can be calculated for the 

separate levels. Considering the entire avifauna, 25 

percent of the species are definitely extinct. Should 

the small grebe humerus prove to represent an extinct 

form, the percentage would be raised to 33. Although 

these figures are too indefinite to give an accurate age 

determination, at least they serve to indicate that the 

Manix avifauna is entirely Pleistocene. This indication is, of course, borne out by the species themselves. 

It is also strongly indicated that the avifauna of at 

least the upper 23 feet is of the upper Pleistocene. 

Whether the lower beds represent the same stage of the 

Pleistocene cannot definitely be determined on the basis 

of these fossils.

LITERATURE CITED

Buwalda, John P., 1914, Pleistocene beds at Manix in the

eastern Mohave Desert region: Univ. Calif. Pub. Bull.

Dept. Geol. v. 7, p. 443-464, pis. 22-25. 

Compton, Lawrence V., 1934, Fossil bird remains from the

Manix Lake deposits of California: Condor v. 36, p. 166-

168, 1 fig. 

Howard, Hildegarde, 1946, A review of the Pleistocene birds of

Fossil Lake, Oreg.: Carnegie Inst. Washington, Pub. 551,

p. 141-195, 2 pis.

1949. New avian records for the Pliocene of California: 

Carnegie Inst. Washington, Pub. 584, p. 177-199, 3 pis. 

Miller, Loye, 1944, A Pliocene flamingo from Mexico: Wilson 

Bull., v. 56, p. 77-82, 2 figs.

1950. A Miocene flamingo from California: Condor, v. 52,

p. 69-73, 1 fig. 

1952, The avifauna of the Barstow Miocene of California.

Condor, v. 54, p. 296-301, 2 figs. 

Wetmore, Alexander, 1924, Fossil birds from southeastern

Arizona: Proc. U. S. Natl. Museum, v. 64, no. 5, p. 1-18,

9 figs.

————1933, Pliocene bird remains from Idaho: Smith. Misc. 

Coll., v. 87, no. 20, p. 1-12, 8 figs.

————1944, Remains of birds from the Rexroad fauna of the 

Upper Pliocene of Kansas: Univ. Kan. Sci. Bull., v. 

30, no. 1, p. 89-105, 19 figs.

PLATE 50
PLATE 50

FIGURES 1-7.—Phoenicopterus minutus Howard, new species (p. 202). Type, Los Angelas County Museum 2445. 1 and 2, Tarsometatarsus, anterior and external views, respectively. 3-7, Tibiotarsus: 3, internal view of distal end enlarged to show contour; 

4, internal view; 5, posterior view; 6, external view; 7, anterior view. All views X 1 except fig. 3, X 2.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 2G4 PLATE 50

PHOEJMCOPTERUS M1NUTUS HOWARD, NEW SPECIES