The Condor94:172-180
01 ‘he Cooper OrnithologicalSociety 1992

IS THE POO-ULI A HAWAIIANHONEYCREEPER(DREPANIDINAE)?’
H. DOUGLAS PRATT
Museum of Natural Science,Louisiana State University,Baton Rouge,LA 70803-3216
Abstract. The Poo-uli (Melamprosopsphaeosoma), discovered on Maui in 1913, wasoriginally believed to be a Hawaiian honeycreeper(Drepanidinae). Doubts as to the validityof this classificationprompted an investigation of the defining charactersof the subfamily
and the possible position of M. phaeosomawithin it. The Drepanidinae are monophyleticwith a suiteof certainand possiblesynapomorphiesthat clusterthe group,but Melamprosops
lacksall of thesecharacters.Hawaiian honeycreepershave a distinctive odor which the Poouli lacks. Its tongue has prominent rearward projections whereas drepanidine tongueslack“lingual wings.” Most drepanidines lack the usual passerinepredator-responsebehaviors
but M. phaeosomaexhibits them. Vocalizations of the Poo-uli do not resemblethose of anyof the three vocal groupingsof Hawaiian honeycreepers.The color pattern of M. phaeosoma
is unique among native Hawaiian birds. Phenotypic charactersthus provide no basis forinclusion of Melamprosopsin the Drepanidinae; its relationshipsare unknown.
Key words: Poo-uli; Maui; Drepanidinae; drepanidine odor; avian tongues;Hawaiian
honeycreepers;
Melamprosops phaeosoma.

INTRODUCTION
The Poo-uli (Melamprosops phaeosoma) is a recently discovered Hawaiian native bird (Casey
and Jacobi 1974) with a restricted range in therainforests of the northeastern slope of Haleakala, Maui (Scott et al. 1986). The bird is a small
passerine (length ca. 14 cm) with a short, thick,and vaguely finchlike bill that superficially resemblesthat of Ciridops anna (Casey and Jacobi1974), a Hawaiian honeycreeper, and those ofsome small tanagers (pers. observ.). Two study
skins with tongues are preserved (Casey and Jacobi 1974). They are dark brown above, buffy
below, with rufous-tingedflanks and a broad blackmask (see illustration in Pratt et al. 1987). Bothskins are now believed to be in immature or
subadult plumage. Breeding adults observed in1986 were plain gray above, white below, witha sharply defined and prominent black mask andlacked most of the rufous and brown tones (A.
Engilis, P. Ching, pers. comm.). The Poo-uli has
been considered endangered since its discovery(Casey and Jacobi 1974), but its population has
now declined to critically low numbers that inhabit a tiny remnant of a range that was already
restricted at discovery (Mountainspring et al.
1990). Thus, additional anatomical material is

I Received 30 May 1991. Accepted 23 September
1991.

unlikely to become available and any assessmentof the systematicposition OfMelamprosops must
be basedon existing specimensand observationsof live birds.
Casey and Jacobi (1974) initially placed thisgenusand speciesin the Hawaiian honeycreepers(Drepanidinae), apparently on the basis of supposedoverall resemblancesand probably also on
geographic probabilities. Melamprosops wasconsidered an offshoot of Amadon’s (1950) genus Loxops (Caseyand Jacobi 1974), which Pratt(1979) regardedasa polyphyletic assemblagenow
dispersedamong five genera (AOU 1983). Pratt(1979) and Berger(198 1) consideredthe positionof Melamprosops among the Drepanidinae uncertain but Amadon (1986), without giving any
supporting evidence, saw“no goodreasonto hesitate to place Melamprosops in the Drepanidinae.” The following discussionspresent several
reasonsfor such hesitation.
MONOPHYLY

OF THE DREPANIDINAE

Any argument as to whether Melamprosops is a

Hawaiian honeycreeper is compromised unlessthe group can be shown to be monophyletic. As
in Darwin’s finches, another oft-cited avian example of adaptive radiation, the casefor monophyly of the Drepanidinae is weak (Baptista andTrail 1988). Perkins (1893) was the first to suggest that the Hawaiian native finches and honeycreepersbelonged to a single taxon. His hy-~1721

POO-ULI SYSTEMATICS

pothesis was widely (and rather uncritically)
accepted, although Bryan and Greenway (1944)
considered the group possibly diphyletic. Amadon (1950) statedthat monophyly was “evident,
chiefly as a result of Perkins’ field work” butignored the primary character of depranidine
odor, upon which Perkins’ (1893, 1903) hypothesis was based. Anatomical studies by Beecher(1953) Bock (1960) James et al. (1989) Raikow(1976, 1977a, 1977b, 1978), Richards and Bock
(1973) and Zusi (1978) demonstrated a remarkable uniformity underlying the spectacularadaptive radiation of externally visible charactersamong Hawaiian honeycreepers. This uniformity is consistent with monophyly (Raikow
1977b), but none of these studies identified any
characterthat clustersthe Hawaiian honeycreepersalone, and none included Melamprosops. Bock
(1978) described several features of the tongue
skeleton shared by M. phaeosoma with drepanidines, cardueline finches, and some other passerines.The tongue musculature also has several“drepanidine features,”most ofwhich are “sharedwith cardueline finchesand somewith other nineprimaried oscines” (Bock 1978). Bock claimed
that these “features not only support the inclusion of Melamprosops phaeosoma in the Drepanididae, but provide further support for themonophyly of the family.” The similarities hecites, however, must be regarded as primitive
characters that carry no phylogenetic information. Zusi (in Amadon 1986, pers. comm.) foundthe interorbital septum of M. phaeosoma to beof the general type found in cardueline finches
and Hawaiian honeycreepers (Zusi 1978), but
did not demonstrate that this type represents a
synapomorphy.
These anatomical studies plus behavioral andecological (Pratt 1979; van Riper 1980, 1987)
and biochemical research (Sibley and Ahlquist
1982, Bledsoe 1988) produced a consensusthat
the Carduelinae are the honeycreepers’ closest
relatives. A recent genetic study (which did notinclude Melamprosops) based on proteins provided support for monophyly of the Hawaiian
honeycreepers, but not for the cardueline/drepanidine relationship (Johnsonet al. 1989). Nevertheless, I herein consider that relationship tobe well establishedand show that most Hawaiian
honeycreepers possesstwo certain, and otherpossible, synapomorphies, but that Melamprosops and the enigmatic genus Paroreomyza do
not share them.

173

CHARACTER REVIEW
Drepanidine odor. Perkins’ (1893) suggestionof

monophyly of the Hawaiian honeycreeperswas
basedalmost entirely on a characterthat hasbeen
denigrated or ignored by recent workers. He noted that the native Hawaiian finches possessthe
same distinctive and peculiar odor characteristicof the drepanidine nectar-feeders and insectivores. Virtually all collectors of Hawaiian birds
noticed the scent, rather like that of old canvas
tents, and their reports are remarkably concordant. By sniffing randomly arranged series of
specimens of various passerine birds placed in
an opaque cloth bag, A. Engilis and I tested eachother’s abilitv to detect the odor and found that
we could consistently identify drepanidine specimens on that basis alone. Becausethe scent iseasily picked up on the fingers and transferredto specimensthat might not originally have possessedit, investigations based on old specimens
are potentially misleading. However, abandoned
nests retain the odor indefinitely (Perkins 1903,
Bryan 1908, pers. observ.) and thus can be used
to investigate the distribution of the odor among
species. Odor intensity varies within species(Perkins 1903, pers. observ.) and perhaps seasonally (Henshaw 1902). It may be totally lacking
in some individuals, especially in species that
inhabit drv habitats (Fisher 1906). I have foundthe odor to be most noticeable in specimensfrom
very wet areas.For example, specimensof Hemignathus virens that I collectedon the dry leeward
slope of Mauna Kea on the island of Hawaii had
only a faint scent, whereas those of the same
speciestaken in the rainy Volcano area on thesame island had a pronounced odor. These observationsare consistentwith the probability thatthe odor is contained in the uropygial secretions
used in preening. In wet areas and during rainyseasons,birds would require more frequent application of water-repellent oils.
Variations notwithstanding, the odor has beenreported in nearly all drepanidine speciesbut notin any other native or introduced birds living inthe same habitats. Perkins (1893, 1901, 1903)
reported “drepanidine odor” in Chloridops kona,
Rhodacanthis palmeri, Loxioides bailleui, Psittirostra psittacea, Pseudonestor xanthophrys,
Loxops coccineus, Hemignathus virens, H. parvus, H. sagittirostris, H. obscurus, H. munroi,
Palmeria dolei, and Drepanis jiinerea (taxonomy

updated). From my own experience I can add

174

H. DOUGLAS

PRATT

Vestiaria coccinea, Himatione sanguinea, andOreomystis bairdi. A. Engilis (pers. comm.) detected the odor in 0. mana. The only supposedly
drepanidine genuswhosemembers definitely lackthe odor is Paroreomyza (Perkins 1903, pers.
observ.), although it is very weak or lacking inmost specimensof Telespiza (Fisher 1906, pers.
observ.).
I searchedcarefully for a similar odor among
specimensof all other families of nine-primariedoscineshousedat the Louisiana State University
Museum of Natural Science, where they would
not have had contact with drepanidine specimens. Although a few other taxa have odd scents,
no other passerinesthat I have examined smell
like Hawaiian honeycreepers.Importantly, I canfind no similar odor among the Carduelinae. Because this trait is novel in the cardueline/drepanidine clade as compared to an outgroup of
all other passerines,is unique to the Drepanidinae within the group, and is present in nearly
all, if not all species,it can be considered a synapomorphy (“canvas odor” as opposed to “nocanvas odor”) of the Hawaiian honeycreepers.
Despite reluctance among many contemporary
ornithologiststo acceptodors as taxonomic characters, drepanidine odor is useful, particularly
becauseosteologicaland myological studieshave
thus far failed to demonstrate unequivocal
monophyly of the Drepanidinae. Some have suggestedthat a chemical analysis would be necessary before sucha charactercould be used. However, if we can say that a bird is “red” without
a spectrographicanalysis, then we can say thatit smells like an old tent without subjecting it togas chromatography (the challenge of doing so
in this case has so far proved insurmountable).
Non-quantitative characters are not necessarily
invalid, and this one is particularly importantbecause it is the historic foundation of the hypothesis of drepanidine monophyly.
Melamprosops phaeosoma apparently lacks
drepanidine odor. A. Engilis and I independently
examined both the type and the paratype andagree that they have no such scent. Of course,
the presenceof drepanidine odor in these specimens would not be very meaningful becauseof
the possibility of postmortem acquisition of thescent from researchers’fingers. However, its absence is telling. The lack of odor is unlikely to
be only the result of small sample size or rainfallrelated variation becausethe entire range of the
Poo-uli lies in an extremely wet area (Scott et al.

1986) where the odor would probably be pronounced. Nor can its absencebe attributed to theimmaturity of the two specimens (although the
ontogeny of drepanidine odor has not been investigated)becauseyoung birds would likely havepicked up the scentfrom the adults during brooding or from the nest. Engilis and I found no traceof drepanidine odor in the two Poo-uli nestsnow
in the Bemice P. Bishop Museum collection. Thisis significant because some very old specimensof drepanidine nests, especially those collected
in wet localities, retain the characteristic scent.
Tongue morphology. Another synapomorphy
clustering the same drepanidine genera as theirodor can be seen at the proximal end of the corneous tongue. In his classic survey, in which
tongues of 118 passerinesrepresenting a broad
sample of families are illustrated, Gardner (1925)
described the “generalized passerinetongue” asending posteriorly “in a free edgewhich is deeply
concave, with the concavity looking caudad andarmed with many sharp conical spineswhich arefirm in texture but bend readily.” The sides of
the concavity are elongated into a pair of caudal
projections now called “lingual wings” (fide D.
Homberger, pers. comm.). Lingual wings arepresent in all passerine tongues illustrated by
Gardner (1925) except those of a sunbird (Nectariniidae) and two Hawaiian honeycreepers(Hemignathus procerus and Psittirostra psittatea). A third drepanidine, Telespizacantans, appears from Gardner’s (1925) illustration to have
lingual wings, but Raikow (1977b) found that thedrawing may have been based on a desiccatedspecimen and that T. cantans also lacks them.
Subsequent studies have shown lingual wings
presentin all passerinetaxa exceptNectariniidae(Schamke 1932) and Drepanidinae (Raikow
1977b), although the projections may be very
short in some of the Meliphagidae (Schamke
193 1, Dorst 1952). Distally, drepanidine tongues
reflect the well-known adaptive radiation in billmorphology in the group, but all variations foundin unequivocal Hawaiian honeycreeperslack lingual wings (Fig. 1). Genera not shown in Figure
1 possesstongues resembling one or another of
thoseillustrated. The rolled tubular type (Gadow
1899) is present in nearly identical form in Vestiaria (Raikow 1977b), Drepanis (Rothschild
1893-1900), and Palmeria (Wilson and Evans
1890-l 899, Henshaw 1902). Nontubular tongues
that resemble those shown for Telespiza andLoxioideshave been describedfor the other finch-

POO-ULI SYSTEMATICS

A.

B.

Loxioides

Telespizo

cantonsC.

boilleuiOreomystis

mono

Oreomystls

boirdiG.

coccineus

E.
D.

F.

Psittirostro

Pseudonestor

psittocea

xonthophrys

loxopsI. Hemignathus

J.

HimotioneM.

sogittirostrissonguinea

L.

w

175

Melomprosops

Hemignothus

phoeosomo

Proximal+ellisianus

procerus

L PI:zio”;zF Distal

FIGURE 1. Representativetonguesof birds classifiedas Hawaiian honeycreepers:A basedon Gardner (1925)
with alterations from Raikow (1977b); B, E, and J after Gadow (1899); C, G, H, I, and N after Richards andBock (1973); D and L after Gardner (1925); F after Frohawk (in Rothschild 1893-1900); K after Bock (1972);
M after Bock (1978).

billed genera Rhodacanthis (Gadow 1899) and
Chloridops(Amadon 1950). Thus, the tongue is
one of the few anatomical features of Hawaiian
honeycreepersfor which we have data from all

genera. Raikow (1977b) compared the tongues
of drepanidine finches with those of both cardueline and emberizine finches and showed thatthe drepanidines differed only in lacking lingual

176

H. DOUGLAS PRATT

L\-._>_

irostrapsittacea

lespiza

can tans

Leucosticte

FIGURE 2. Comparison of representative tonguesof drepanidine finches (right) and other finch-billed taxa
(left), after Raikow (1977b).

wings (Fig. 2). Becausethis characteris restricted

to the Drepanidinae within the cardueline/drepanidine clade and is not present in the outgroupof other nine-primaried oscines, it can be regarded as a synapomorphy. The presence of acomparable condition in the ten-primaried Nectariniidae probably is the result of convergence.
The tongue of Melamprosops phaeosoma isunlike that of any other passerineyet described(Bock 1978). It is thick and fleshy, with a shallow
groove on the dorsal surfacethat expandsdistally
to form a spoonlikedepression,the sidesof whichhave a few blunt serrations.Bock (1978) regarded
these serrations as vestiges of the laciniae thatform the tube of the rolled tubular drepanidine
tongue, implying that it evolved from that typeof tongue. The tip of the tongue is rounded andsmooth, lacking any trace of the fringed tip orbifurcation characteristic of most passerine
tongues(Gardner 1925, Bock 1978). The tip bears
little resemblance to the “seed-cup” tongues of

cardueline and some drepanidine finches and isapparently adapted to a diet of terrestrial mollusks (Baldwin and Casey 1983). Such a specialization is unique among Hawaiian passerines. Posteriorly, the tongue exhibits a prominent
pair of caudal projections armed with large tubercles and thus differs from the tongues of Hawaiian honeycreepersin the one respectthat setsthem apart from those of other nine-primariedoscines.It is notable that Paroreomyza montana,
which, like M. phaeosoma, lacks drepanidine
odor, representsthe only other supposedly drepanidine genus to possesslingual wings (Richards and Bock 1973).
Behavior. Observers accustomed to continental avifaunas have long noted that Hawaiian honeycreepersare seldom attracted by “squeaking,”
the auditory lures widely used to attract birds(Home1 1991, pers. observ.). Many species,including Loxioidesbailleui, Hemignathus munroi,
Pseudonestorxanthophrys,Loxops coccineus,L.

POO-ULI SYSTEMATICS

caeruleirostris,Oreomystis mana, and 0. bairdi,
virtually never “squeak up.” In my own experience and that of A. Engilis (pets. comm.), only
the nectar-feeding species such as Himationesanguinea, Vestiaria coccinea,and Palmeria dolei do so with any regularity. Perkins (1903) reported possibly comparable behavior in both
now-extinct speciesof Drepanis. The amakihis
Hemignathus virens,H. kauaiensis, and H. parvus, which occasionally feed on nectar, sometimes respond to spishing but usually do not. In
contrast such other Hawaiian passerinesas Corvus hawaiiensis (Perkins 1903) Chasiempis
sandwichensis(pers. observ.), and Myadestesobscurus(pers. observ.) readily squeak up.
Responseto squeak lures is believed to be related to predator mobbing (Emlen 1969). True
mobbing (Curio 1978) has never been reported
in any drepanidine genus other than the enigmatic Paroreomyza (Perkins in Wilson and Evans
1890-1899, Bryan 1908, Pratt 1979). Some ofthe same nectar-feeding honeycreepersthat respond to squeak lures also engagein “approachand-follow” behavior directed at humans. Suchbehavior hasbeen noted in Palmeria dolei, Drepanis funerea, and Vestiaria coccinea (Perkins
1903, pers. observ.), all nectar feeders, but has
not been reported in the finchlike or primarily
insectivorous species.Although few avian predators are now present, the existence of drepanidine bones in fossil owl pellets (Olson and James1982) showsthat predation was probably an important selective force in the evolution of Hawaiian honeycreepers. Thus, the apparent absence of mobbing behavior in most species ispuzzling, particularly when such behavior has
been documented in many cardueline finchesandis believed to be innate (Hinde 1954, Altmann1956). Whether the lack of response to squeaklures and the absence of predator mobbing aresynapomorphiesof the Drepanidinae cannot yet
be determined becauseinsufficient data are available on the occurrenceof suchtraits in passerines
generally. Altmann (1956) found no taxonomic
correlation with the presenceof mobbing behavior. Nevertheless, any speciesthat differ strikingly from most drepanidines in thesebehaviors
should not be uncritically classified with them.
The Poo-uli appears to be such a species.Engilis (1990) reported both response to auditorylures and approach-and-follow behavior, but actual predator mobbing by the Poo-uli has notbeen observed.Although the nectar-feeding hon-177

eycreepers(currently Tribe Drepanidini) exhibit
similar behaviors, Melamprosopsphaeosomahasnone of the other charactersof that group (Pratt
1979).
Vocalizations. Avian vocalizations can provide meaningful inferences about relationships
at lower taxonomic levels. Mundinger (1979)
showed that despite the influence of learning,some calls of cardueline finches are useful taxonomic charactersat the family level. Isler andIsler (1987) stated that tanager genera could be
identified in the field by vocalizations alone. Pratt(1979) found that Hawaiian honeycreeperscan
be clustered on the basis of vocalizations into
groups (the tribes of the 1983 AOU Check-list)that coincide with those based on other characters. Most drepanidine speciesfall into three large
vocal groupings: the finchlike species(Psittirostrini), the red-and-black nectar feeders (Drepanidini), and the thin-billed insectivores (Hemignathini). If Melamprosopsphaeosoma could beshown to vocally resemble any of these groups,
the casefor including it among the Drepanidinaewould be strengthened.
The songs of drepanidine finches have often
been likened to those of various carduelines. The
song of Telespiza cantans is “loud, melodious,and canarylike, even to the inclusion of trills,”
and its call notes are also “melodious, some resembling those of the canary” (Berger 198 1:112)
a cardueline. Fisher (1906) said the calls were“linnetlike,” another cardueline comparison.
Telespiza ultima also has a “canarylike” song,as do (or did) Loxioidesbailleui (Pratt et al. 1987)
Chloridopskona (Munro 1960) and Psittirostra
psittacea (Perkins 1903, Pratt et al. 1987). The
exact meaning of “canarylike” is usually unstated. Berger(198 1:116) wasmore specificin statingthat the song of Telespiza ultima has a “distinct
canarylike quality, containing trills, whistles,andwarbles.” Each of the canarylike songsis distinct
and recognizablein its own right, but all are long,complex, unstereotyped,and include varied, frequency-modulated, sustained notes.
The Drepanidini whose vocalizations havebeen described(Himatione, Palmeria, Vestiaria,
and Drepanis) have long been recognized as a
vocally distinct species-groupdespite wide divergence inter se (Perkins 1903). They resemble
the canarylike songs in complexity and lack ofstereotypy (Ward 1964) but as a group are characterized by peculiar bell-like or metallic qualities to the notes and often include squeaky or

178

H. DOUGLAS PRATT

I

I

I

1

I

I

2

Set

FIGURE 3. Sonagram(Libraryof Natural Sounds,CornellLaboratoryof Ornithology,No. 5 125)of call notes
and a shortsongsegmentutteredby an immature Poo-uli. Recordedby the author 27 July 1975 in Upper
Hanawi watershed,Koolau ForestReserve,Maui.
mechanical-sounding phrases (Perkins 1903,
Pratt et al. 1987). This group also lacks a clearcut distinction between calls and songs.Calls of
the Drepanidini usually represent notes that also
are elements of the more complex songs, andsome species,such as Vestiaria coccinea,exhibit
a virtual continuum between single-notecalls andcomplex songs(pers. observ.).
In the Hemignathini, canary-like vocalizations
are present only as subsongs(Pratt 1979). The
primary songs of all speciesare simple, rather
stereotypedwarbles or trills. The notes lack any
bell-like or metallic qualities and sound muchthe same as the trills and warbles that form partsof the more complex songsof the Psittirostrini(Pratt 1979, Pratt et al. 1987). Call notes of the
Hemignathini are obviously different from primary songsboth in function and complexity andare not incorporated into the longer vocalizations. This vocal grouping includes Hemignathus, Loxops, Oreomystis, and Pseudonestor.
Pseudonestorwas placed in the Psittirostrini inthe 1983 AOU Check-list, but Pratt (1979) considered it to belong to the Hemignathini, partly
on the basis of vocal similarities. Sonagrams ofsome hemignathine songsare given by Scott etal. (1979).
Melamprosopsphaeosomadoesnot fit into anyof the three vocal groupings of Hawaiian honeycreeperseven though its call notes resemble
those of several other Maui forest birds (Pratt etal. 1987, Mountainspring et al. 1990). The songcomprisesshort, sharp, chips identical to the single-note calls but faster paced with some variation in pitch and rhythm (Engilis 1990). Before
nesting birds were observed in 1986, such vocalizations were not even recognized as the pri-mary song. Mountainspring et al. (1990) statedthat a “developed song similar to that of other
Hawaiian honeycreepers has never been observed,” and Pratt et al. (1987) also considered
the song unknown, but both describe vocalizations that in retrospectare probably fragmentary
songs.Figure 3 shows such a short song utteredby a juvenile. The full adult song, which comprises a more extensive series of similar notes(Engilis 1990), has never been recorded. This
songdoes not remotely resemble that of any Hawaiian honeycreeper. Although these observations do not preclude the possibility that the Poouli is a Hawaiian honeycreeper,they provide no
support for such a classification. The only othersupposeddrepanidine whosevocalizations do not“fit in” is the problematical Paroreomyza montuna (Pratt 1979).
Coloration. Among Hawaiian honeycreepers,
plumage color and pattern varies lessamong speciesthan suchfeaturesasbill morphology.Amongthe Hemignathini are many green species(Prattet al. 1987) that differ in bill shapeand little else.
Indeed, certain speciesof Hemignathus, Loxops,
and Oreomystis present considerable problems
for field observers (Scott et al. 1979, Pratt et al.
1987). The Psittirostrini are nearly all colored inolive green and yellow, whereasthe Drepanidini
are known as the “red-and-black group” (Perkins
1903).
The colors and pattern of the Poo-uli are unlike that of any previously known Hawaiian honeycreeper (Casey and Jacobi 1974). The coloration of both the juvenile (brown and buff) andadult (gray and white), without any trace of yellow, are distinctive. Casey and Jacobi’s (1974)
color photograph, taken inside a yellow tent

POO-ULI SYSTEMATICS(T.L.C. Casey, pers. comm.), is misleading inmaking the bird look green. Thus, plumage color

and pattern provide no basis for inclusion of
Melamprosopsphaeosomaamong the Drepanidinae.

DISCUSSION AND CONCLUSION
The above review shows that the classificationof Melamprosopsphaeosoma among the Drepanidinae has virtually no phenotypic basis. Indeed. these charactersindicate that its relationships probably lie elsewhere. The Poo-uli does
not look, smell, act, or sound like a Hawaiian
honeycreeper, and its tongue lacks a derived statethat clustersall drepanidine generaexceptParoreomyza (which may also be incorrectly classified,
but to which Melamprosops is probably not related). If future biochemical studiesindicate that
Melamprosopsis drepanidine after all, some hypothesiswill be required to explain the near absence of phenotypic expression of the relationship. At present, the only unequivocal statementthat can be made about the affinities of the Poouli is that it is a nine-primaried oscine of uncertain affinities (“incertae sedis”). Speculation as
to its actual relationships would, at present, bebaseless.Becauseit casts doubt upon the most
likely possibility, my hypothesisof what it is not
is a first step toward determining what it is.

179

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.__.
BOCK,W. J. 1972. Morphology of the tongue apparatus of Ciridops unna (Drepanididae). Ibis 114:

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BRYAN,E. H., JR., AND J. C. GREENWAY,JR. 1944.
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