NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
186 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, III
The authors wish to express their appreciation of the valuable assistance ren-
dered by Mr. Akbar Ali, B.Sc. (Agri.) of the Chemical Section, in carrying out the
analyses.
BOTANICAL NAMES OF FODDERS AND TREES MENTIONED IN THIS PAPER.
English or Vernacular names.
Rice straw
Oats
Toria
Maize
Wheat
Barley
Chari
.
.
.
.
.
.
Sugarcane
Mash
Maina
Kulth
Bamboo
Sirs
Khirk
Bhera
Kich
Karal
Dhaman
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Botanical names.
Oryza sativa.
Avena sativa.
Brassica campestris var. toria.
Zea Mays.
Triticum sativum (vulgare).
Hardeum Vulgare.
Andropogon Sorghum.
Saccharum officinarum.
Phaseolus radiatus.
Medicago sativa.
Dolichos biflorus.
Dendrocalamus strictus.
Albizzia Lebbek.
Celtis australis.
Terminalia belirica.
Grewia berulaefolia.
Bauhinia purpurea.
Grewia oppositifolia.
REFERENCES.
Lander (1926). Agricultural Journal of India 21, 5.
Lander and Lal Chand Dharmani
Ditto
Ditto
Ditto
Ditto
Ditto
(1924),
(1927)
(1928)
(1929)
(1930)
(1925),
Mem. Dept. of Agri.
Pusa Bulletin 158.
India,
ditto
ditto
ditto
ditto
Chem. Ser. 7, 4.
9, 3.
9, 7.
10, 5 and 6.
10, 7.
Warth (1926). Mem. Dept. Agri. India, Chem. Ser. 9, 2.
DIGESTIBILITY TRIALS ON INDIAN FEEDING STUFFS
187
TABLE III.
Chemical composition.
Name of the feed
Rice straw
Green oats
Maize grain
Toria cake
Moisture
%
6.20
72.68
12.20
5.31
Dry matter
%
93.80
27.32
87.80
94.69
Ash
%
15.47
1.89
1.70
7.14
Fat
%
0.82
0.62
3.85
11.83
Crude fibre
%
34.23
9.57
1.67
10.61
Protein
%
2.25
1.38
9.75
32.00
Nitrogen free
extract
%
41.03
13.86
70.83
33.11
Mineral matter in 1,000 lbs. of the feed.
Kangra
Rice
straw.
Phos-
phates
P ² O 3
2.30
Calcium
CaO
3.76
Sodium
Na ² O
4.11
Potas-
sium
K ² O
21.65
Magne-
sium
MgO
2.29
Manga-
nese
Mn ² O 4
0.26
Alumi-
nium
Al 2 O 3
1.49
Iron
Fe 2 O 3
0.58
Sulphate
SO 4
1.15
Chlori-
des
Cl.
••
Insoluble
residue
84.34
188
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, III
TABLE IV.
Comparison of data on Kangra rice straw with similar data from other places.
Locality
Chemical composition per 100
grammes of oven dried
rice straw.
Pusa
....
Bangalore
....
American
....
Kangra
....
Comparison of digestibility
coefficients.
Pusa Old .
Pusa New
....
Bangalore
American
Kangra
....
Amounts digested from 100
lbs. dry substance.
Pusa
....
Bangalore
....
American
....
Kangra
....
Dry matter
100.00
100.00
100.00
100.00
47.00
52.37
53.54
..
42.73
52.37
53.54
..
42.73
Ash
17.03
17.59
15.68
16.49
..
..
..
..
12.61
..
..
..
2.08
Fat
1.25
0.86
1.51
0.87
60.20
41.34
43.41
23.00
46.67
0.52
0.38
0.35
0.41
Crude fibre
35.74
30.91
36.22
36.49
72.00
72.96
70.43
59.00
60.72
25.89
21.67
21.37
22.16
Protein
2.43
2.79
4.22
2.40
..
..
11.17
22.00
—19.16
..
0.31
0.93
—0.46
Nitrogen free
extract
43.57
47.88
42.38
43.74
44.10
41.95
57.71
46.60
42.40
18.28
27.60
19.50
18.55
Organic
matter
82.97
82.41
84.32
83.51
57.10
58.84
60.61
49.97
48.59
48.82
49.97
42.14
40.58
Carbo-
hydrates
79.29
78.79
78.59
80.23
..
61.22
62.53
52.00
50.73
48.54
49.27
40.87
40.71
DIGESTIBILITY TRIALS ON INDIAN FEEDING STUFFS
189
TABLE V.
Dietary standards.
Period
9-11-29 to 3-12-29
Ditto
Ditto
15-12-29 to 11-1-30
Ditto
Ditto
15-2-30 to 25-2-30
Ditto
Ditto
13-3-30 to 29-3-30
Ditto
Ditto
No. of
heifer
122
128
133
122
128
133
122
128
133
122
128
133
Average
of daily
body-
weight
lbs.
446
440
356
397
382
320
412
413
304
426
452
361
Food eaten per day
lbs.
Rice straw
Do.
.
Do.
.
Rice straw
{ Maize grain
{ Rice straw
Maize grain
{ Rice straw
Maize grain
{ Rice straw
Toria cake
{ Rice straw
Toria cake
{Rice straw
Toria cake
{ Rice straw
Green oats
{ Rice straw
Green oats
{ Rice straw
Green oats
. 6.1
. 5.4
. 4.8
, 5.0
. 4.0
. 4.5
. 4.0
. 3.7
. 4.0
. 8.1
2.0
. 9.1
. 2.0
. 6.6
. 2.0
. 3.7
. 10.9
. 3.7
. 10.9
. 2.9
. 8.7
Per 100 lbs. of
food
starch
equiva-
lents
18.41
16.91
20.92
..
..
..
..
..
..
..
..
..
Protein
Negative
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
Albumi-
noid
ratio
1:
8
8
8
} 23.0
} 22.1
} 18.4
} 9.6
} 10.3
} 7.9
] 62.8
} 64.8
47.4
Daily
nitrogen
balance
in grm.
—6.87
—6.55
—5.19
10.05
8.32
12.46
10.56
14.94
19.97
—3.76
—3.43
—2.80
Staroh
equiva-
lents
per day
1.12
0.91
1.00
4.01
4.16
3.90
3.45
3.69
3.18
2.00
2.10
1.86
Protein
per day
lbs.
Negative.
„
„
0.21
0.22
0.24
0.48
0.49
0.51
0.05
0.05
0.06
190
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, III
TABLE VI.
Digestibility factors.
Period
9-11-29 to 3-12-29
Ditto
Ditto
15-11-29 to 11-1-30
Ditto
Ditto
15-2-30 to 25-2-30
Ditto
Ditto
13-3-30 to 29-3-30
Ditto
Ditto
No.
of
heifer
122
128
133
122
128
133
122
128
133
122
128
133
Average
of
daily
body
weight
lbs.
446
440
356
397
382
320
412
413
304
426
452
361
Food eaten
per day
lbs.
Rice straw 6.1
„ „ 5.4
„
„
4.8
Rice straw 5.0
Maize grain 4.0
Rice straw 4.5
Maize grain 4.0
Eice straw 3.7
Maize grain 4.0
Rice straw 8.1
Toria cake 2.0
Rice straw 9.1
Toria cake 2.0
Rice straw 6.6
Toria cake 20
Rice straw 3.7
Green oats 10 9
Rice straw 3.7
Green oats 10.9
Rice straw 2.9
Green oats 8.7
Digestibility Coefficients
Dry Matter
41.79
40.83
45.56
61.34
65.46
65.90
52.16
51.87
53.83
50.93
52.03
59.22
Ash
8.51
13.10
16.22
19.04
23.37
14.06
11.51
14.84
11.20
19.48
18.18
27.86
Fat
40.00
50.00
50.00
73.68
78.94
72.22
83.86
84.37
86.20
70.00
70.00
62.50
Crude fibre
60.30
57.84
64.03
65.73
68.33
70.89
63.42
63.36
65.19
58.26
59.13
67.75
Protein
—14.29
—25.00
—18.18
42.00
44.90
51.06
58.53
57.64
64.53
21.74
21.74
31.58
Nitrogen free
extract
42.00
40.54
44.67
68.24
73.07
72.86
53.77
53.07
54.90
54.49
57.15
62.34
Dry Matter
2.39
2.07
2.05
5.03
5.06
4.60
4.95
5.41
4.35
3.27
3.34
3.02
Nutrients digested per day
lbs.
Ash
0.80
0.11
0.12
0.16
0.18
0.09
0.16
0.23
0.13
0.15
0.14
0.17
Fat
0.02
0.02
0.02
0.14
0.15
0.13
0.26
0.27
0.25
0.07
0.07
0.05
Crude fibre
1.26
1.07
1.05
1.17
1.10
0.95
1.89
2.11
1.61
1.34
1.36
1.24
Protein
—0.02
—0.03
—0.02
0.21
0.22
0.24
0.48
0.49
0.51
0.05
0.05
0.06
Nitrogen free
extract
1.05
0.90
0.88
3.33
3.42
3.17
2.14
2.33
1.85
1.64
1.72
1.49
DIGESTIBILITY TRIALS ON INDIAN FEEDING STUFFS
191
TABLE VII.
Showing details of daily nitrogen balance in grammes.
Period
9-11-29 to 3-12-29
.
Ditto
Ditto
15-12-29 to 11-1-30
.
Ditto
Ditto
15-2-30 to 25-2-30
Ditto
Ditto
13-3-30 to 29-3-30
Ditto
Ditto
No. of
heifer
122
128
133
122
128
133
122
128
133
122
128
133
Feed
Rice straw
Do.
Do.
Rice straw and
Maize grain.
Do.
Do.
Rice straw and
Toria cake.
Do.
Do.
Rice straw and
green oats.
Do.
Do.
Intake
Straw
grm.
9.96
8.82
7.84
8.17
7.35
6.04
13.23
14.86
10.78
16.96
16.96
13.47
Concen-
trates grm.
..
..
..
28.30
28.30
28.30
46.45
46.45
46.45
..
..
..
Outgo
Dung
grm.
11.90
10.57
9.04
20.70
19.43
16.51
24.36
26.42
20.26
12.86
13.35
9.41
Urine
grm.
4.93
4.80
3.99
5.72
7.90
5.37
24.77
19.95
17.00
7.86
7.04
6.86
Total
intake
grm.
9.96
8.82
7.84
36.47
35.65
34.34
59.68
61.31
57.23
16.96
16.96
13.47
Total
outgo
grm.
16.83
15.37
13.03
26.42
27.33
21.88
49.12
46.37
37.26
20.72
20.39
16.27
Balance
grm.
—6.87
—6.55
—5.19
10.05
8.32
12.46
10.56
14.94
19.97
—3.76
—3.43
—2.80
A VETERINARY ENTOMOLOGY FOR INDIA, PART XIV.*
BY
T. BAINBRIGGE FLETCHER, R.N., F.L.S., F.E.S., F.Z.S.,
Imperial Entomologist to the Government of India,
AND
S. K. SEN, M.Sc., F.E.S.,
Assistant Veterinary Research Officer, Imperial Institute of Veterinary Research,
Muktesar (lately Assistant to the Imperial Entomologist).
(Received for publication on the 10th April 1031.)
(With Plate IX.)
The Tabanidae—also known as Gad-flies, Horse-flies, Dans—comprise a very large
family of Diptera characterized by thick-set bodies, large heads and very large eyes.
In the female the eyes are separated by a fairly broad band (dichoptic), while in the
male the eyes are contiguous (holoptic). In life the eyes frequently exhibit
brilliant golden-green and purple markings, but after death the colour of the eyes
rapidly changes to dark-brown, until scarcely a trace of the markings remains.
The frontal portion of the head is usually furnished with small dark longitudinal or
transverse callosities or calli, which are of importance in classifying the flies. The
antennæ are porrect and consist of three segments, the third segment being
annulated ; the arista is absent.
The Family includes about 2,000 described species of which about 300 are
palaearctic, about 300 North-American, the remainder being natives of South
America, India, Africa and other tropical countries [Efflatoun Bey, 1930]. In 1927
Senior-White estimated a total of 126 species for the Indian Region, and Kröber
and others have since recorded a few more, raising the Indian total to probably
about 135 described species, but undoubtedly many more await discovery within
Indian limits.
* (Continued from Vol. IV, Part IV of the Jour. of the C. B. for Animal Husbandry and Dairying
in India.)
( 192 )
EXPLANATION OF PLATE IX, TABANID FLIES.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
Tabanus indianus, Ricardo.
„
rufiventris (♀), Fb.
Chrysops flavocinctus, Ric.
Haematopota roralis, Fb.
Chrysops designatus, Ric.
„
pellucidus, Fb.
Tabanus nibidus, Wied.
Corizoneura longirostris, Hardwicke.
„
taprobanes, Wlk.
Tabanus orientis, Wlk.
Chrysops flavipes, Meig.
„
stimulans, Wlk.
Tabanus brunnipennis, Ric.
Gastroxides ater (♀), Saund.
„
„ (♂), Saund.
Tabanus rufiventris (♂), Fb.
„
ditaeniatus, Meig.
„
subcallosus. Ric.
„
virgo, Wied.
Haematopota hindostani, Ric.
Tabanus tenens, Wlk.
„ macer, Big.
„
striatus, Fb.
Chrysops dispar, Fb.
PLATE IX.
VETERINARY ENTOMOLOGY FOR INDIA
193
The presence of water is necessary for the majority of Tabanidae, so that dry
and arid tracts are inhabited only by some rare—evidently migratory—species
[Seguy, 1924]. According to Surcouf [1921] the regions that have yielded the largest
number of Tabanids, both in respect of genera and species, are those that enjoy
a moderately elevated temperature and possess some forests or mountainous reliefs
with water and a varied fauna. Galli-Valerio [1930] says that the abundance of
Tabanids does not depend on the presence of cattle, but varies with the year and
the place, for Tabanids leave their normal habitats only if man and animals pass
through them, when the flies may follow them for long distances. In most localities
in India, Tabanids are common during the Rains, the adult females and occasionally
the males visiting human habitations where they may be seen on the walls and
window panes, sometimes even attacking the occupants.
The females only are blood-suckers, the food of the males consisting of the
nectar of flowers, the sap oozing from plants and frequently the sweet juice of over-
ripe fruits dropped on the ground [Surcouf, 1924]. Williston [1908] says that the
females also feed on the honey-dew secreted by plant-lice and scale-insects and on
similar substances. As originally observed by Portchinsky and later confirmed by
other observers, several species of Tabanidae have the curious habit of swooping
over the surface of pools and other collections of water, evidently for drinking
purposes. The females are almost exclusively parasites of warm-blooded
animals, their usual hosts being horses, cattle, mules, buffaloes, camels, elephants
and sometimes man. Surcouf [1923] refers to certain genera of Tabanids
(Adersia, Brodenia and Lesneus) which in their adult stage have the appearance of
Œstrids and which do not appear capable of taking nourishment on account of the
extreme reduction of their buccal apparatus, so that, like the Œstridæ, they
probably live as parasites in their larval stages. Members of these genera,
however, are not known to occur in India. It is relatively simple to capture the
females while they are in the act of sucking blood or ovipositing, but the males are
relatively seldom seen ; they may sometimes be swept with a net from grass and
other vegetation or noticed at rest on tree-trunks or walls.
To those having to deal with stock under field conditions in India, the Tabanids
are conspicuous by reason of their relatively large size and the severity of their
bites, it being not unusual to observe blood freely flowing from the wounds inflicted
by them. This is often accentuated by the large number of individual Flies which
attack. It is not unusual to be able to catch fifty or more Tabanids on one animal
in an hour.
The different species of Tabanids have a curious predilection for the site in the
host's body from which to feed. Thus, according to Patton and Cragg [1913], in
B
VETERINARY ENTOMOLOGY FOR INDIA
195
experienced in inducing many of the bred specimens to feed. It was found that
bright sunshine is essential, and that it is usually several days after hatching before
the first meal is taken ".
Cross and Patel [1921] found that Tabanids preferred to bite surra-infected
animals rather than a healthy one and that buffaloes were the favourite hosts,
donkeys being the least preferred. They are of the opinion that Tabanids find
their hosts by means of sight and not by smell, and this view would seem to find
support in the observations made in South Africa where it is stated that several
species of Tabanids are attracted to dummy animals (Jl. Dept. Agric. Union S.
Africa, VIII ; 1923).
It seems possible that advantage of this habit may be taken by using decoy-
traps such as have recently been adopted in Africa for trapping Tsetse Flies. That
Tabanids are attracted by moving objects, even a railway train, is a common
observation when travelling in India and they may often be carried long distances
in this way.
As regards the feeding habits of Tabanids in captivity, observations at Pusa
(vide Report of Entomological Section for 1915-16) showed that when bred females
of Tabanus nemocallosus, starved under humid conditions for 24 hours after emer-
gence, were allowed to bite under cover of test tubes the shaven and moistened
skin of a goat, they sucked blood within five minutes. Further they were capable
of resisting starvation for 5 days in humid surroundings, showing a marked
tendency to drink water, and if the habit of sucking sugary food was acquired, the
blood-sucking habit was resumed with reluctance. Nieschulz [1927] in Java,
observed that T. rubidus and T. striatus could live for 70 days in captivity and that,
if opportunities were given, they sucked blood on an average rather oftener than
every second day.
The actual mechanism of biting in the Tabanidæ has been discussed by Surcouf
and his account is briefly reproduced below. The part of the skin to be attacked
being first selected by feeling it with the proboscis, the labella are retracted, the
stylets are evaginated and enter into action in the following fashion: the mandibles
are rotated inwards under the action of the adductor muscles and the cutting blades
penetrate obliquely in the tissues, then they are brought back to their original
position by the abductors; their action is comparable to that of a section of a saw
worked by alternate movements. During this time the maxillæ are alternately
pushed forward and brought back in position by their corresponding muscles in.
two different directions and at each retreat the barbed blades cut through the
tissues. According to Nitzulescu [1926], the buccal armature of Tabanids more
closely resembles that of Phlebotomus (" Sand-flies ") than that of mosquitos.
B 2
196 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, III
As a rule, Tabanids attack animals standing in the sun, as we have frequently
observed while collecting these flies in various localities in India. Writing of the
Tabanids of Pusa, Isaac [1925] states that Tabanus macer is generally active from
mid-day to evening, attacking animals standing in the sun, whilst T. rubidus is
active when the day is bright and warm. On the other hand, T. tenens, which is
the most abundant species at Pusa, was found by him to be most active at sunset
just before dark, when the females came in large numbers to cattle. It would be
interesting to recall here the experience of workers in this respect in certain other
countries. Williston [1908] working in U. S. A., observed that none of the Tabanids
was active on dark, cloudy days, though some were partial to shady woods, but
they were most plentiful about cattle and horses while the sun was shining. On
the other hand, Lutz [1923], in Brazil (where he records a total of about 300
species), states that Tabanids are more frequent in the shade in forests or when the
sun is low and that some species are even crepuscular in habits. In India some
species occasionally come in to light at night and it is probable that some Tabanids
are normally nocturnal.
Several members of this family have been shewn to be capable of transmitting
Surra mechanically. Of these mention may be made of Tabanus striatus in the
Philippines (Mitzmain), T. striatus and T. rubidus, especially the latter, in Java
(Nieschulz), and of T. rubidus, T. nemocallosus in India (Cross, Patel, Kahan Singh,
Abdulla Khan). Of other Tabanid-borne diseases of animals, reference may be
made to Anthrax, conveyed by T. striatus (Mitzmain, Nieschulz), T. rubidus and
Chrysops flavicinctus (Nieschulz); hæmorrhagic septicæmia from buffalo to buffalo
(Nieschulz); and sarcocystis (Sergent). Under natural conditions, the existence of
a relationship between outbreaks of trypanosomiasis on the one hand and the
relative abundance of Tabanids on the other is strikingly illustrated by the following
information abstracted from the Annual Reports of the Egyptian Veterinary Service
for 1916 and 1917 (Trop. Vet. Bull., VIII, 274 ; Sept. 1920): " For a number of
years past Mason had noted that the Tabanidæ which carried trypanosomiasis, viz.,
T. taeniola and T. ditaeniatus, were usually very numerous during the fly season in
the Suez Canal Zone, along the Ismailia Canal and in Eastern Sharqûya ; this was
what happened in 1915 and a considerable number of cases of trypanosomiasis
occurred in Army Camels in consequence. During 1916 Tabanids were fortunately
not observed in the above localities although the number of camels had greatly
increased. No cases of trypanosomiasis apparently occurred in the Canal Zone
during the year.
" For the same reason the Wadi Natrûn District remained free in 1916. On
the other hand, both the above species of Tabanids were extremely numerous as
VETERINARY ENTOMOLOGY FOR INDIA
197
usual in the Western Oases and a considerable number of cases of trypanosomiasis
occurred in camels, but none was observed in any other animals."
The Tabanidæ are divided into two sub-families and the Indian forms are com-
prised under ten genera.
These are differentiated as follows :—
Underside of tip of hind-tibia with a pair of (often con-
spicuous) spines or spurs; ocelli usually present
. Pangonianæ.
Hind-tibia without spurs at tip ; ocelli absent .
. Tabaninæ.
Pangonianœ (Partly adapted from Senior-White, 1927).
1. Proboscis very long, longer than the length of
abdomen
Proboscis not unusually long, shorter than the
length of abdomen
......
2. Third antennal segment with an acute spine on first
annulation
Third antennal segment without spine
3. First and second antennal segments long, first seg-
ment equal or sub-equal in length to second seg-
ment
First antennal segment long, second short
4. Tibiæ normal
Tibiæ large and flattened. Whole aspect of insect
bee-like
........
Tabaninæ (From Senior-White, 1927).
1. Apical portion of third antennal segment of three
divisions
Apical portion of third antennal segment of four
divisions
2. Third antennal segment simple, no basal tooth or
process
........
Third antennal segment with a basal tooth or
process
3. Antenna arising from a frontal tubercle, third seg-
ment cylindrical. Palpus thickened basally, bent,
apically pointed
......
Corizoneura, Rond.
2
Gastroxides, Saund.
3
Chrysops, Meig.
4
Silvius, Meig.
Melissomorpha, Ric.
Haematopota, Meig.
2
3
4
Udenocera, Ric.
198 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, III
Antenna not arising from a frontal tubercle, third
segment conical. Palpus elongate, subulate
4. Antenna not arising from a prominent tubercle.
Frontal calli usually present
....
Antenna arising from a prominent tubercle. No
frontal calli
Diachlorus, O. S.
Tabanus, Linn.
Neotabanus, Ric.
Udenocera, Diachlorus, Neotabanus, Silvius and Melissomorpha are each repre-
sented by a single Indian species and none of these is recorded from the Plains of
India.
The genus Gastroxides includes two Indian species. So far, Gastroxides ornatus
is known only from Ceylon and little information would appear to be on record
concerning its bionomics. G. ater has been recorded from Central India, Calcutta,
Pusa, Coimbatore, Chapra, Fyzabad and Surat. The larvae of G. ater breed in
hollows of trees and the flies are said to come to light at night and to be probably
nocturnal in their habit of flight (Report of Imperial Pathological Entomologist for
1915-16). More recently, Isaac [1925], at Pusa, has published some notes on
G. ater. The full-grown larva is about 24 mm. in length and yellowish white in
colour. The larval growth is very slow and the larva is able to resist starvation
for long periods. The pupa is blackish in appearance and is about 22 mm. long
and occurs in the same site where the larva is found. The pupal stage lasts six
days and the adults emerge in June and July. There is only one brood in a year,
hibernation occurring in the larval stage. The mouth-parts of the female are
apparently adapted for piercing and sucking, although the flies do not appear to
have been observed actually to suck blood. The eggs or the young larvae have not
been observed.
The genus Corizoneura (commonly known as Pangonia) includes two Indian
species, but Ricardo recognizes, in addition, a variety.
As would appear from the localities of their occurrence, both C. taprobanes
and C. longirostris are almost exclusively denizens of hilly tracts. (It is more than
probable that the record of occurrence of C. longirostris in Allahabad is an error).
Very little is known concerning the bionomics of these species, but at Muktesar
(alt. 7,500 ft.) C. longirostris makes its appearance about the latter part of July and
disappears by the first week of September and during this period they may fre-
quently be observed to suck nectar from flowers of the species, Roscoea purpurea,
of the family Scitamineae. Imms [cited by Tetley, 1917-18], working at Bhowali
(Kumaon ; 5,000 ft.), similarly records having observed flies of this species " on the
basis of forests towards the end of the rainy season, feeding on flowers of the orders
VETERINARY ENTOMOLOGY FOR INDIA
199
Scrophulariaceæ and Labiatæ by thursting their proboscis into them, poising them-
selves in the air during the process ". Nothing is known concerning the young
stages of C. longirostris, but in one instance about 150 eggs were dissected out from
a gravid female at Muktesar and each egg measured about a millimetre in length.
Observations made at Kasauli [Mitter, 1917-18] and Muktesar would appear to
indicate that the females are capable of sucking blood, which they do while hover-
ing by making repeated darts at the host, and in certain instances the actual
presence of blood has been detected in the midgut of dissected flies. It may be
mentioned that the long proboscis of the fly which meets the eye of the casual
observer is merely the labium, which never functions in the act of biting, the actual
stylets being much shorter and more or less hidden away in the labium. This latter
organ, however, is probably well-adapted for scooping out sugary fluids (e.g.,
nectar of flowers), being paired and honey-combed at the tip, in the fashion of a
double spoon. C. laprobanes, however, sucks blood only when settled on its host.
The species of Tabanids which the field veterinary worker is most likely to en-
counter are comprised under the genera Haematopota, Chrysops and Tabanus, the
Indian species included in those genera numbering approximately 31, 11 and 75 re-
spectively. Senior-White [1927] has given keys for the identification of these species,
but the Veterinary worker in India is not likely to require more than a generic
reference so that it seems unnecessary to reproduce these keys here.
(To be continued).