VP-NRLF

THE LIBRARY

OF

THE UNIVERSITY
OF CALIFORNIA

PRESENTED BY

PROF. CHARLES A. KOFOID AND
MRS. PRUDENCE W. KOFOID

WITH THE PUBLISHER'S COMPLIMENTS.

A Monograph

OF THE

Anopheles Mosquitoes of

India

By

S. P. JAMES, M.B., I.M.S.,

Formerly with the Royal Society's Malaria Commission in India,

AND

W. GLEN LISTON, M.D., I.M.S.,

Of the Plague Research Laboratory, Parel, Bombay.

Calcutta
Thacker, Spink & Co

1904

LONDON: W. THACKER & CO., 2, CREED LANE, E.G.

CALCUTTA :
PRINTED BY THACKER, SPINK AND CO.

PREFACE.

THIS book has been written at the request of some of
our fellow-workers in India, and, for that reason, we need not
apologise for its publication. Its scope is indicated in the
title. We have attempted to treat the subject clearly, and to
describe the different species in such a manner that any
specimen which may be encountered will be easily identified.
In our opinion this is the most important requirement of any
book dealing with mosquitoes, and, in connexion with it, we
venture to hope that our coloured plates, which are strictly
accurate in detail, will be found helpful. We are much
indebted to our friend Dr. Turkhud, of Bombay, for having
drawn them, under our direction, with so much care and
skill.

Although we have not felt able to adopt Mr. Theobald's
new classification of " Anopheles," we have given a brief
account of his system, and have added, under the title of each
mosquito described, the generic and specific names by which
the insects are known to him.

In common with all medical men in the tropics we owe
a debt of gratitude to Professor Ray Lankester for having
initiated the work of which Mr. Theobald's admirable treatise
is the outcome, to Mr. Theobald himself, and to Colonel
Giles, I.M.B.

M364118

CONTENTS.

PART I.— GENERAL.

PAGE.

CHAPTER I. — A general account of mosquitoes ... ... 3

CHAPTER IT. — The collection, mounting, examination and identification

of "anopheles" mosquitoes and their larvse ... 29

CHAPTER III. — The habits of Indian "Anopheles" ... ... 41

CHAPTER IV. — The classification of "Anopheles" ... ... 59

PART II.— SYSTEMATIC.

GROUP I. — A. barbirostris ; A. nigerrimus ... ... ... 77

GROUP II. — A. leucophyrus ; A. punctulatus ... ... ... 82

GROUP III. — A. pulcherrimus ; A. willmori ... ... ... 86

GROUP IV. — A. karwari ; A. fuliginosus ; A. jamesi ; A. maculipalpis ;

A. theobaldi ; A. maculatus ... ... ... 89

GROUP V. — A. jeyporiensis ; A. listoni ; A. culicifacies ... ... 101

GROUP VI.— A. rossi ; A. stephensi ... ... ... 109

GROUP VII. — A. turkhudi ... ... ... ... 115

GROUP VIII. — A. lindesayi ; A. gigas ... ... ... 117

GROUP IX. — A. aitkeni ; A. immaculatus ... ... ... 112

GROUP X. — A. culiciformis ... ... ... ... 122

LIST OF ILLUSTRATIONS.

COLOURED PLATES AT THE END OP THE BOOK.

I. Diagram of a female " anopheles " mosquito.

II. Anopheles barbirostris.

III. ,, nigerrimus.

IV. „ pulcherrimua.
V. „ fidiginosus,

VI. „ jamesi.

VII. „ maculipalpis.

VIII. „ theobaldi.

IX. ,, jeyporiensis.

X. ,, listoni (or fluviatilis).

XI. ,, culicifacies.

XII. ,, rossi.

XIII. ,, stephensi.

XIV. ,, turkhitdi.
XV. ,, lindesayi.

HALF-TONE PLATES FACING THE TEXT.
I. Eggs and larvae of " anopheles " and " culex " mos-

quitoes ... to face page 7

II. Larvae and pupae of "anopheles" and "culex "mosquitoes „ 9

III. Adult male and female "anopheles" and "culex"

mosquitoes ... IA

» » i>

IV. The larva of A maculipalpis ... ... ... 35

V. „ larvae „ A. barbirostris and A. fuliginosus ... „ „ 78

VI. „ „ „ A. rossi and A. stephensi .. ... )t }) 37

VII. „ „ „ A. listoni and A. jeyporiensis ... „ „ n 1Q3

VIII. „ „ „ A. culicifacies and A. turkhudi ... „ „ „ 108

IX. Microphotographs of wing scales ... ... „ „ n HO

X- ,, ,, „ ,, ... ... „ „ M 113

Map of India showing the distribution of some species of " ano-
pheles " mosquitoes ... ... ... ... J} „ M 41

Diagrammatic drawing of the chief characters of A. leucophyrus „ „ „ 83

„ „ „ „ „ „ „ A. punctulatus „ „ „ 85

„ „ „ „ „ „ A, karwari ... „ „ „ 89

,, ,, ,, ,, ,, ,, ,, A. aitkem ... ,, ,, ,, 120

,, ,, „ ,, larva of A. culiciformis „ ,, ,, 122

List of illustrations.

FIGURES IN THE TEXT.
Fig.

1. Eggs of mosquitoes of the genera Panoplites, Stegomyia and Psoro-

phora ... ... ... 7

2. Larvae of Chironomus, Ephemera and Corethra ... ... H

3. Different forms of scales ... ... ... ... 16

4. To show the method of mounting a mosquito ... ... 26

5- „ „ „ ,, „ preserving mosquitoes in tubes ... ... 27

6. ,, ,, ,, ,, ,, examining mosquitoes ... ... 28

7. ,, „ „ ,, ,, keeping mosquitoes alive in bottles ... 38

8. Eggs of " anopheles " mosquitoes ... ... ... 39

9. Chart showing the seasonal prevalence of A. culicifacies and A. rossi

in the Punjab ... ... ... ... ... 43

10. Plan of Royal Artillery lines in Mian Mir to show breeding places of

" anopheles " mosquitoes ... ... ... ... 50

11 Wing of A. leucophyrus ... ... ... ... 83

12. „ ,, A. karwari ... ... ... 90

PART I.

MONOGRAPH

OF TH'E

ANOPHELES MOSQUITOES

OP INDIA.

CHAPTER I

A GENERAL ACCOUNT OF MOSQUITOES

I

jEFORE commencing the study of any particular
kind of mosquito it is necessary to know something
of the general characters, life history, and structure
of this important family of insects.

Mosquitoes or gnats (Culicidce) belong to the
order of insects known as Diptera. As is well-known, a typical
member of the class Insecta has four wings, but it is characteristic
of members of the order Diptera that the hinder pair of wings are
so reduced in size as to form only small knobs called " balancers "
or halter es, so that Diptera are often spoken of as " two- winged
flies." Other important characteristics of members of this order
are that they possess piercing and sucking mouth parts, and that
they undergo complete " metamorphosis " — a term which is ex-
plained by Glaus in the following manner :—

" The more complete the agreement between the just-born young and the adult sexual animal
so much the greater will be the duration of the embryonic development and the more complicated
the developmental processes of the embryo. The post-embryonic development will, in this case,
be confined to simple processes of growth. When, however, the embryo is born in an immature
condition and at a relatively low state of organization, the post-embryonic development will be
more complicated, and the young animal, in addition to its increase in size, will present various
processes of transformation and change of form. In such cases the just-hatched young, as opposed
to the adult animal, is called a Larva and develops gradually to the form of the adult sexual
animal. The development of larvas, however, is by no means direct and uniform, but is compli-
cated by the necessity for special contrivances to enable them to procure food and to protect
themselves ; sometimes taking place in an entirely different medium, under different conditions of
life. This kind of post-embryonic development is known as metamorphosis."

The phenomena of metamorphosis are exceedingly well shown
in the life history of frogs and in that of most insects. The differ-
ent stages through which mosquitoes pass before they reach the

[3

How to distinguish Mosquitoes from other Flies

adult state may, for example, be briefly described in the following
way:—

The adult mosquito lays its eggs on the surface of water. The
eggs float on the water for some days (two to four), after which
time they hatch and permit of the escape of the larva.

The larva is a free swimming, worm-like animal, which eats
greedily and grows rapidly, casting its skin several times in the
process, till it reaches its full development. At this stage it
suddenly changes its form ; casting its skin, the worm -like larva
assumes a comma shape, and so becomes the pupa or nympha.

During the pupal period the insect ceases to eat ; profound
anatomical changes take place within the pupal skin, whereby the
masticatory mouth parts of the larva are converted into the suctorial
apparatus of the adult insect or imago. After a certain number
of days the pupa-case ruptures, and the adult insect is liberated,
furnished with wings and legs adapted for a life in the air.

The Diptera have been divided into two great groups, termed
Orthorrhapha and ^yclorrhapha, according to the manner in which
the pupa-case splits to permit of the escape of the perfect insect.
In the Orthorrhapha, which includes the Culicidoe (mosquitoes), the
ChironomidcB (midges), the Simulidce (sand-flies', the Cecidomyidce
(gall-midges), the Mycetophilidce (fungus-midges), the Tipulidce
(daddy-long-legs), the TabanidcB (horse-flies), etc., the pupa-case
splits longitudinally down the median dorsal line. In the Cyclor-
rhapha, which includes the Syrphidce (hoverflies), the Oestridce
(bot-and warble flies), the Muscidce (houfee flies, tsetse flies, blue and
green bottle flies, flesh flies, etc.), the perfect insect escapes by the
splitting off of a cap from the head end of the pupa.

The members of some of the above families are not infrequently
mistaken for mosquitoes, especially the ChironomidcB or midges, the
Cecidomyidce or gall-midges, the Tipulidce, the Simulidce, and the
Psychodidce or owl-midges. Mosquitoes may, however, be easily
distinguished from any other flies by the following characters : —

(1) They possess a long sucking proboscis.*

(2) The veins on their wings are covered with scales.

(3) The arrangement of their wing-veins is characteristic and

different from that of the members of any other family.

* Except in the genera Corethra and MocJilonyx.

4]

Mr. Theobald's Classification of Mosquitoes

The Chironomidce or midges have neither a long sucking pro-
boscis nor scaly wings.

The Cecidomyidce or gall-midges have the body and wings
covered with hairs, not scales, and the venation of the wings is
simple, no fork-cells being present.

The Psychodidce or owl-midges have the wings densely covered
with hairs, not scales.

The Simulidce, Tipulidce, etc., have the wing-veins bare, without
hairs or scales.

There is really no difficulty, therefore, in distinguishing mos-
quitoes from other flies which seem to resemble them. \

The family Culicidce is divided, for the purposes of classification,
into a number of sub-families, genera, and species. Up to the
present, entomologists have based these subdivisions entirely upon
differences in the adult insects, but there are good reasons for
thinking that differences between mosquitoes in the larval or imma-
ture stages of their existence are also of great importance for the
purposes of classification and identification. The larvae of only a
few species are, however, accurately known, and at present we must
be content to follow, at any rate in the main, the somewhat
unscientific methods of classification adopted by entomologists.

Mr. F. V. Theobald, who is the greatest authority upon
mosquitoes, divides them into the following sub-families : —

1. The Anophelina containing at present 11 genera and about 80 species.

2. The Megarhinina „ ,, „ 2 „ ,, ,, 20 ,,

3. The Culicina „ „ .„ 17 „ „ numerous „

4. The Joblotina „ „ „ 1 genus „ 1

5. The Heptaphlebomyina,, „ ,, 1 » >» 1 »

6. The Aedeomyina „ „ „ 20 genera „ about 55

7. The Corethrina „ ., ,, 2 ,, ,, ,, 18 ,,

The characteristics of the adult insects upon which these sub-
families are based are as follow : —

1. Palpi long in both sexes ; about as long as proboscis Anophehna.
•2. Palpi long in both sexes ; shorter than the proboscis

in the female ; proboscis long and bent ... Megarhinina.

3. Palpi long in the male, very short in the female ... Culicina.

4. Palpi as in Culicina. Seven instead of six longitudi-

nal veins on the wings ... ••• Heptaphlebomyina.

5 Palpi as in Culicina. Metanotum with hairs and scales Joblotina.

[5

Stages of Metamorphosis : the Egg

6. Palpi very short in both sexes ... ... Aedeomyina.

1. Proboscis short and not formed for piercing .. Corethrina.

Many of these sub-families are of importance to the worker on
tropical diseases only in so far that some knowledge of their
characteristics is essential to enable him to distinguish them from
the mosquitoes which he especially desires to study. The Megar-
hinincB are rare and cannot easily be confused with any other mem-
bers of the Culicidce on account of their large size, brilliant colour,
and long curved proboscis. The greater number of species have
also a curious caudal tuft of brilliantly coloured hair-like scales at
the end of the abdomen on each side. The Aedeomyince and Core-
thrince are at present of no importance from a pathological point
of view ; the former are easily recognised by their very short palpi
in both sexes, and the latter by their very short non-piercing pro-
boscis which somewhat resembles that of the Tabanidce or gad-

o

flies. The Heptaphlebomyince and JoUotince may, for all practical
purposes, be considered as belonging to the Culicinae. Each of
these sub-families contains but one species, which, in the case of
Heptaphlebomyina, was placed in a distinct sub-family because it
had seven longitudinal wing veins instead of six, and in the case
of Joblotina because the metanotum carried hairs and scales.

By far the most important of the sub-families are the Ano-
phelina and the Culicina, which contain all the species of mosqui-
toes known to be connected with the transmission of disease. In
the former sub-family are included all the mosquitoes usually known
as "anopheles," and in the latter most of those usually known as
" culex." In fact, for the student of tropical medicine, no very ela-
borate classification of the family Culicidce is necessary or advisable,
and a knowledge of the differences between the two groups " Culex"
and " Anopheles," together with a knowledge of the more important
characteristics of a few of the genera included in the sub-family
Oulicina are all that are essential before the task of the identifi-
cation of individual species is commenced. These points will be
referred to in the following more detailed account of the different
stages in the metamorphosis of mosquitoes.

THE EGG OR OVUM

The eggs of most "culex" mosquitoes, before being deposited by
the female, are collected together, in the angle made by the crossing

61

PLATE I.

FII;. 1.

I

Fir;. 4

I- ir,. (5.

FIG. 7.

Ftc. 8.

Tail of Culex Larva

Fro. 9.

PLATE I. Fig. 1.—" Anopheles" eggs. Natural size: Fifir. 2. -Egg of A. roisi, magnified, showing the upper surfac°, the lateral floats, and the
beaded rim ; Kg. 3.— Lateral view of the same ; Fig. It.— Raft-like masses of " Culex " eggs, natural size ; Fig. fi.—H. raft mass of " Culex " eggs,
magnified ; seen from above ; Fig. 6. — Lateral view of the same ; Fig. 7.— Four " Culex " eggs, greatly magnified ; Firj. 8.— Posterior extremity of
" Anopheles " larva showing sessile stigmatic apparatus and " palmate hairs" • Fig. .9.— Posterior extremity of " Culex" larva.

The Eggs of " Culex " and " Anopheles "

of the insect's hind legs, so as to form an elongated boat-shaped
mass consisting of several hundred eggs joined to one another by
their edges. When this egg-boat or egg-raft has been constructed
the insect allows it to drop into the water, where it floats as a
small oblong boat-shaped body somewhat raised at each extremity
(PI. I., Figs. 4, 5, 6). The shape and character of these egg-rafts
vary in different genera. In the genus Culex (sub-family Culicina)
they are broad and more or less oval in shape ; in the genus Tcenior-
hynchus (sub-family Culicina} they are said to be very elongated
and to resemble a racing skiff in shape (Stephens and Christo-
phers) ; in the genus Coreihra (sub-family Corethrina), the eggs are
collected together in flat, round, jelly-like masses.

The eggs of all " anopheles " mosquitoes, on the other hand,
as well as those of a few " oule* " moquitoes (viz., those of the
genera Stegomyict, Panoplites, Psorophora and Janthinsoma of the
sub-family Culicina) are not collected together into a mass of defi-
nite shape before deposition. The reason of this is that the indivi-
dual eggs do not stick together, so that when laid on a solid object
they form only a piled up mass, and when
laid on water they quickly separate from one
another and float as isolated elements (PI. I,
Fig 1 ). Owing to physical causes, the eggs,
when deposited on water, may arrange
themselves in fairly definite star-shaped pat-
terns or in rows, but more frequently they
are scattered irregularly over the surface
of the water. The individual eggs which
compose an egg-raft of " culex " mosquitoes,
are oblong in shape, and broader and more

, -.->, Fig. 1 {after Daniels).

rounded at one end than at the other ( PI.

I, Fig 7). When joined together to form the raft they lie verti-
cally with the narrow end out of the water and the broad end — from
which the larva escapes — submerged. The eggs of mosquitoes of
the genus Panoplites (Fig. la) have one end terminating in a fine
point ( Daniels), and those of the genera Stegomyia and Psorophora
(Fig. 1, I & c) are peculiar in that, besides being more or less oval
in shape, they possess a rim of cells, somewhat resembling the rim
or frill present in " anopheles " eggs.

[7

The Larva

A typical " anopheles" egg (PL I, Figs. 2, 3) is a boat-shaped
body about 07 to I'O mm. in length. The upper surface or " deck "
is flattened, but slightly convex, and is surrounded by a narrow
beaded rim or frill. One end of the egg is slightly deeper and
fuller than the other, and it is toward this end that the head
of the embryo is directed. Along the centre of each side of the
egg is attached an oval ribbed air-containing " float" ( see also
Fig 8). These floats are very characteristic structures and are not
present in the eggs of any other kind of mosquito as yet described.
Their shape and position differ in the eggs of different species of
" anopheles," as does also the width and extent of the beaded rim or
frill already described, and Stephens and Christophers have shown
that it is possible to distinguish the eggs of some species by the
position and characters of these two structures. These distinctions
between the eggs of the various species will be described later.

THE LARVA

The larvae of all mosquitoes are made up of three regions : (1 )
the head, (2) the thorax, and (3) the abdomen. The shape and
characteristics of these three regions differ in the various sub- fami-
lies, genera and even species of mosquitoes, but the characters of
the abdomen afford the readiest means of distinguishing between
the main groups and must therefore be described first. The abdo-
men of all mosquito larvae is divided into nine segments. The first
seven segments closely resemble one another and need not be spe-
cially described. The eighth segment carries the external openings
of the respiratory tubes or trachece, by means of which oxygen is
supplied to the tissues of the larva. In all " anopheles " larvae the
two large tracheae open directly on the upper surface of the eighth
segment by two stigmata which are surrounded and supported by a
complex apparatus (PI. I, Fig. 8). In "culex" larvae, on the other
hand, the respiratory tubes do not open directly at the surface of
the segment, but are prolonged onwards into a projection from the
segment known as the siphon tube (PI. I, Fig. 9). The absence of
a siphon tube in " anopheles " larvae renders their recognition from
among the larvae of all other kinds of mosquitoes an easy matter.
For the identification of the different kinds of " culex " larva? the
length and character of the siphon tube are of great value. Thus

8]

PLATE II.

^'Yii.tura.l size. '•{£
Position of Culex in water

f i i t-m • nkuSh •> -;• ; ~-"-^ _"~* *= -

Enlc.

JEnla.rq&d-

FIG. \.

Position, of Anopheles

in. Wetter-

Fio.

-p size

Fin. 3.

FIQ. 4.

PLATE II. Fig. 1. — Larva of " Culex," showing the position at the surface of the water ; .Figr. 2. — Larva of "Anopheles," showing the same ; Fig.
Pupa of "Culex" ; Fig. It.— Pupa of "Anopheles. "

The Larva of " G2ilex " and " Anopheles'

in larva? of the genus Stegomyia the siphon tube is very short and
thick, and in those of the genus Culex it is long and thin. Ste-
phens and Christophers employ the term " siphoriic index " for the
figure obtained by dividing the length of the siphon tube by its
greatest breadth, and state that for the different species in any
genus this figure is very constant. In Stegomyia larvae, for ex-
ample, the siphonic index is about 2, i.e., the length of the tube is
about double its greatest breadth, in Culex larva? it is about 4, and
in Tceniorhynchus larvae it may be as much as 13.

The ninth abdominal segment is cylindrical in shape and carries
the opening of the anus, around which are symmetrically arranged
the four anal papilla?. On the dorso-lateral surface of certain of the
abdominal segments of " anopheles " larva? characteristic structures
called " Palmate hairs " are present (see PI. IV). Each of these
hairs has a short stalk, to the apex of which are jointed a number
of leaflets, which, when spread out, are arranged somewhat like
the ribs of an umbrella which has been turned slightly inside out,
or perhaps more nearly like the leaf of a cocoanut palm. Two of
these palmate hairs are present on each segment which is provided
with them, and it is chiefly by their means that the larva main-
tains its position close under the surface of the water. They are
not present on the larvae of any other kind of mosquito than
" anopheles."

On account of their presence and on account of the absence of
a siphon tube " anopheles " larva? float in the water immediately
beneath and parallel with the surface film ( PL II, Fig. 2).

On account of the presence of a siphon tube and the absence
of palmate hairs " culex " larva? float considerably below and at an
angle with the surface film (PI. II, Fig. 1 ).

These are the essential differences by which " anopheles " and
" culex " larva? may be distinguished from each other, and it is un-
necessary to describe in detail the differences between any other
regions of the larva? of these two kinds of mosquitoes. The head of
an " anopheles " larva (PI. IV) is more or less rounded in shape
and is covered by a clearly defined chitinous case. The eyes are
situated laterally, and in front of each eye is an eminence which
carries the antenna. A broad band of pigment runs across the
head between the two eminences from which the antenna? arise, and

[9

Some important larval hairs

this carries six branched hairs which project forward over the
head (see PL IV). Arising from the corner of each eminence, and
situated just outside the most external of the six hairs just mentioned,
is a characteristic hair that we have called the " Basal hair. " It is
seen projecting forwards just outside and parallel to the antenna
in Plate VII, fig. .2, A, and in the figures of the larvae of A.
karwari, A. culiciformis, &c. It differs in character in different
species and is of value in the identification of larvae. The anterior
median area of the head is called the clypeus, and it carries on each
side a large bunch of hairs called the whorl organs or " feeding
brushes. " Lying directly over each whorl organ is a hair which
may be called the external frontal hair or external clypeal hair,
and between the whorl organs of each side is a pair of hairs close
together which may be called the median frontal or clypeal hairs.
These four frontal or clypeal hairs project beyond the head and may
be simple or branched. They are of great service in the identifi-
cation of the larvae of different species and will be more particularly
referred to later. In some larvae, e. g., A. turkhudi and A. jeypori-
ensis a third hair called the " Posterior hair, " arises from the
clypeus just behind and between the two frontal hairs of each side.
This hair is also of some service in identification. It is shown in
Plate VII, fig. 2, and in Plate VIII, fig. 2. The sides of the mouth
are formed by the mandibles, and its floor by the maxillae. Each
mandible carries a number of stout teeth, which, working in con-
junction with those of the mandible of the opposite side, serve to
crush the food.

In full-grown larvae the thorax is broader than the head or than
any of the abdominal segments ( PL IV). It carries a number of
branched hairs, and in some species a pair of well-developed palmate
hairs similar to those present on the abdominal segments can be
easily seen.

A few words may be added regarding the movements of larva?
in water and their method of feeding. " Anopheles " larvae change
their position at the surface of the water by a series of very
characteristic jerking, darting movements in a backward direction.
When actually occupied in feeding they lie stationary beneath the
surface film, only their mouth parts moving. " Culex " larvae do
not dart along at the surface in a backward direction as " anopheles "

10]

Movements in water and method of feeding

larvae do, but when engaged in feeding they are propelled slowly
forwards by the action of their mouth parts alone. Both kinds of
larvae, when disturbed, usually wriggle rapidly to the bottom of the
pool, where they lie motionless with their bodies extended. " Ano-
pheles " larvae sometimes do not wriggle to the bottom, but simply
extend their bodies and allow themselves to sink by virtue of their
weight. When rising to the surface the movements of these larvae
are much more jerky than those of " culex."

" Anopheles " larvae feed just beneath the surface film, and,
whilst feeding, the head is rotated so that its ventral surface
lies uppermost, though the body of the larva remains in its

Fig. 2.

original position. This rotation of the head is very character-
istic and is peculiar to the larvae of this kind of mosquito.
" Culex " larvae often feed at the bottom of a pool, moving along

7 ~he Larva of Chironomus, Ephemera, and Dixa

in their natural position and picking up stray bits of food of
all kinds.

The larvae of other flies than mosquitoes are often met with in
water nnd may sometimes be mistaken for mosquito larvae. The
commonest are the larvae of the flies called Chironomus, EpJiemera
and Dixa. Chironomus larvae are often found in large numbers
when the mud at the bottom of a small pool is stirred up. They
are bright red worm -like creatures and are commonly known as
" blood worms." Although their tracheae open externally in a
pair of " respiratory tubes " ( fig. 2 D, d) in appearance they bear
no resemblance to mosquito larvae. The larvae of ephemeral flies
differ essentially from those of mosquitoes in that their air-tubes
do not open externally, so that they obtain the oxygen they re-
quire from the water by means of gills, the presence of which
makes them very easily recognisable (fig. 2 A & B. It should
also be noted that in Corethera larvae (fig. 2, C.) there is no direct
communication of the air-tubes with the external air. The larvae
of this kind of mosquito are very transparent, and are called for
that reason " Phantom larvae." The head is much smaller than
that of any other mosquito larvae. There are four distinct res-
piratory sacs which do not, however, contain air. The larvae have
no spiracles and, except when nearly full grown, no air-tubes. The
four air-sacs simply act as floats, and at no period of larval life is
there any direct communication with the external air. It will be
seen therefore that these larvae are very different from other mos-
quito larvse, and it is doubtful whether the ( *orethrince should be
classified with the true mosquitoes,

Dixa larvae bear a superficial resemblance to " anopheles "
larvae and float just beneath the surface film as the latter do. The
fact that all the segments of Dixa larvae are almost equal in
size, the fact that they have no palmate hairs, and that they
possess four prolegs, by using which they creep up the side of
the vessel in which they are placed, should prevent any difficulty
being experienced in distinguishing these larvae from those of
" anopheles."

THE PUPA OB NYMPH

The pupae of mosquitoes are active creatures, rising and falling
in the water at will. Unlike the larvae, they can sink in the water

12]

The Pupa and the Imago

only by violent exertions with their tails. As soon as these move-
ments of the tail cease, the buoyant pupa floats up to the surface
again. Like the larvae, they breathe air through protruding spiracles ;
but these air tubes, instead of being at the tail end, as in the larva,
are placed on the dorsum of the thorax, as two trumpet-shaped
structures, projecting like horns. (PL II, figs. 3, 4. )

The length and shape of these spiracles enable " anopheles "
pupae to be distinguished from those of " culex."

" Anopheles " pupae have short, stumpy, funnel-shaped spiracles
(PI. II, fig. 4), while those of " culex " are longer, more slender, and
trumpet-shaped (PI. II, fig. 3).

THE ADULT MOSQUITO OR IMAGO

The adult mosquito is divided into three regions: (ij the
head, ( 2) the thorax, (3) the abdomen. To the head are attached
sensory and suctorial appendages ; while to the thorax are attached
the legs and wings. (See Descriptive Diagram of a female anopheles.
Coloured plate No. I. )

The head is rounded and attached to the thorax by a narrow
neck The portion of the head near the neck is called the nape.
Above and in front of the nape is the occiput. In front of the
occiput, and occupying the greater part of the antero- lateral portion
of the head, are the two compound eyes. Immediately anterior to
the eyes, on either side, arise the antennae, which are long, jointed
structures covered with hairs. In the male the antennae are very
prominent hairy organs (PL III, figs. 1,3); in the female they are
less conspicuous and almost devoid of hairs. (PL III, figs. 2, 4).

In front of the antennas will be noted a firm median chitinous
prolongation, the " clypeus." Beneath the clypeus arise the mouth
parts, which consist of seven pieces collectively termed the proboscis.

The mouth parts are : —

{ 1 ) the upper lip, made up of labrum and epipharynx ;
(2) & (3) two mandibles ;
(4) & (5) two maxillae ;

(6) the hypopharynx or tongue ;

(7) the lower lip or labium.

The labium is a grooved structure, within which the other six
mouth parts are enclosed.

[13

The Head, Thorax, and Abdomen

Attached to the maxillae are two maxillary palpi. The palpi
of " anopheles " mosquitoes are very prominent organs, as long as
the proboscis in both sexes, and clubbed at their extremity in the
males. (PI. Ill, figs. 3, 4).

The palpi are less prominent organs in the genera Culex,
Stegomyia, Panoplites, etc., except in the case of the males, in which
they are even longer than the proboscis, but in the females of these
genera they are rather minute structures, just visible to the naked
eye. (PL III, figs. 1, 2).

The thorax is mainly composed of the middle division or
mesothorax ; it is large and convex. Behind the main part of the
thorax, a prominent ridge runs between the bases of the wings ; this
ridge is called the " scutellum." Posterior to the scutellum, a
horse shoe-shaped area is seen ; this is the " metanotum."

Projecting laterally, behind the metanotum, the club-shaped
halteres will be noted.

The abdomen is more slender than the thorax, and consists of
nine segments : eight of these are easily seen, each segment being
composed of a dorsal plate or tergum, and a ventral plate or
sternum, joined together by a soft membrane. The anus opens
on the ventral surface of the eighth segment, while the genital
opening is on the ninth segment, and to this segment are attached
the genital ia.

Attached to the under-surface of the thorax are the six legs,
three on each side (anterior, middle, and posterior pairs of legs).
Each leg consists of the following parts : — Two small segments,
the coxa and trochanter (these cannot be seen from the dorsal
aspect), two longer segments, the femur and tibia, and, lastly, five
tarsal segments. The first tarsal segment is sometimes called the
metatarsus. Between the tarsal segments are the tarsal joints.

The wings of mosquitoes are mapped out with veins which are
covered with scales. These veins have a very definite arrangement,
and a knowledge of the names applied to them is essential in dis-
tinguishing the different species.*

The external or anterior border of the wing is called the costa.

Running parallel with the costa is the first longitudinal vein.

•

* The reader will be greatly helped by following these veins as well as other structures
noted, on the descriptive diagram of a female anopheles (coloured plate No. I).

H]

PLATE 111.

rr~

Fio. 2

Fin. 4.

Fie. 5

Fio. 6.

7/7. Fig 1.— Head of a male " Culex " ; Fig. 2.— Head of a female " Culex " ; fig. 3.— Head of a male " Anopheles " ; Fig. It.— Head of a female
"Anopheles" ; fig. 5.—\ female "Culex," showing the position usually assumed when at rest on a surface,- Fig. 6.— A female,, Anopheles,
showing the position usually assximed when at rest on a surface.

Wing 'venation

Immediately behind and arising about the junction of the inner
with the middle third of this vein is the second longitudinal vein.
After completing about half of its course this vein divides into two
branches, the anterior and posterior branches of the second longi-
tudinal vein.

Behind the second longitudinal vein and arising about the
middle of the wing is the third longitudinal vein.

The fourth longitudinal vein arises at the base of the wing,
and in the last quarter of its course divides into two branches,
anterior and posterior.

The fifth longitudinal vein also arises from the base of the
wing ; at about the middle of its course it divides into two branches,
anterior and posterior.

The sixth longitudinal vein is unbranched, arises from the base
of the wing, and terminates about the middle of the posterior border
of the wing.

Joining these longitudinal veins with one another are certain
transverse veins.

The most important of these transverse veins is the " the
sub-costal " which, arising near the origin of the first longitudinal
vein, passes obliquely forwards and outwards to meet the costa about
the beginning of the outer third of its course. This is the only
transverse vein which is covered with scales.

Joining the first long vein to the origin of the second long

vein is a very short transverse vein, " the marginal transverse vein."

Joining the origin of the third long vein to the second long

vein is " the super-numerary cross vein." The vein joining the

third long vein to the fourth long vein is the " mid cross vein."

The vein joining the fourth long vein to the anterior branch
of the fifth long vein is called " the posterior cross vein."

The first, third, and sixth longitudinal veins are unbranched.
The second, fourth, and fifth long veins divide in their course into
two branches. The areas enclosed between these branches have
received names. The area enclosed between the branches of the
second long vein is called "the first submarginal cell"; that between
the branches of the fourth long vein, " the second posterior cell,"
and that between the branches of the fifth long vein, " the anal
cell. " Names have been applied to the other areas of the wing

[15

Scale Structure

enclosed between the various veins, but for our present purpose
they need not be mentioned. The posterior margin of the wing is
always fringed with long scales, " the wing fringe."

No account of the characters of mosquitoes would be complete
without some remarks on scale structure, the importance of which
has been very ably demonstrated by Mr. Theobald.*

Head scales. — Some or all of the following forms of scales may
be found on the head of a mosquito : —

1. ''Upright forked scales" (fig. 3, 2) are found chiefly

towards the nape. These scales have long stalks with
an expanded fan -like head, the angles of which project
outwards like the prongs of a fork. They stand out
from the surface upon which they are inserted.

2. " Narrow curved scales" (fig. 3, 3, are long curved

scales tapering to their extremities ; the body of the
scale is expanded at its widest part to from ^ to ^ of
the length of the scale. These scales are chiefly found
projecting from the occiput.

3. "Flat scales" (fig. 3,1) have a narrow pointed base;

the body of the scale rapidly expands from the base.
The extremity of the scale is broad, with a flat or
slightly convex edge. These scales, in contrast to
the scales mentioned
above, lie closely
applied to the sur-
face from which
they arise and over-
lie one another like
the slates on a roof.
They are found on
the dorso-lateral
surface of the head.
Thoracic scales. — Five forms of thoracic scales are described by
Mr. Theobald.

1. Narrow hair-like curved scales ^fig. 3, 4)

2. Narrow curved scales (fig. 3, 3 ).

* "A monograph of the Oulicidae of the world" by Fred. V. Theobald, M.A., F.E.S.,
British Museum (Natural History), Vols. I & II, 1901 ; Vol. Ill, 1903.

Fig. 3.

Scales on the Abdomen, Wings, Halteres, &c.

3. Spindle-shaped scales (figs. 3, 6).

4. Flat scales similar to those on the head (figs. 3, 1).

5. Long twisted scales (figs. 3, 8).

Abdominal scales. — In all " culex " mosquitoes and in one
" anopheles " mosquito (Aldrichia error, Theobald) the abdomen is
covered with overlapping flat scales. In some " anopheles " there
are no scales on the abdomen, in others a few small flat scales
occur in patches, and in others the abdomen is densely covered with
scales of various forms.

Wing scales. — In all mosquitoes the veins of the wings are
covered with scales which vary in shape and size in different
parts of the same wing, Mr. Theobald describes the following
forms as occurring on the wings of " anopheles " mosquitoes :
1, lanceolate (figs, 3, 9) ; 2, long and narrow ; 3, large and
inflated. On the wings of other kinds of mosquitoes some of the
scales may be very large, flat and much expanded (Panoplites
figs. 3, 5) ; broad and asymmetrical (Aedeomyia ) ; parti-coloured
and pyriform or inflated (Mucidus) ; or broad and elongated
( Tceniorhynchus).

Leg scales. — In nearly all mosquitoes the legs are clothed
evenly writh flat scales, which form a complete covering. In a few
cases hair-like scales, which occur in tufts, may be present, as in
Sabethes.

Scales on the proboscis, palpi, and antennas. — The scales on
the proboscis are usually small and flat, but in some " anopheles "
they stand out very distinctly at an "angle to the surface (A. sinensis,
dc.). The palpi in some mosquitoes may also be densely scaled, as
well as the basal and first two or three of the following segments.

Scales on the halteres. — Mr. Theobald makes no mention of
scales being present on these structures, but their presence and
character can be readily made out in most species of " anopheles."

In the classification of mosquitoes Mr. Theobald relies almost
entirely upon scale structure for the distinctions between different
genera, and in one case he has used this character alone for the
formation of a sub-family (Joblotina). The genus Stegomyia was
separated from the old genus Culex by reason of the fact that only
two forms of scales, viz., upright forked and flat scales, are present

Mr. Theobalds new Classification of " Anopheles "

on the heads of members of this genus, instead of the three kinds
usually found on the heads of most other "culex" mosquitoes ; and
the genera Panoplites ( = Mansonia), Tceniorhynchus and others by
reason of their peculiarly shaped wing scales. Mr. Theobald has
recently adopted a new classification of " anopheles" mosquitoes
based almost entirely on scale structure, in which he divides these
mosquitoes under 11 new genera as follows : —

Genus 1. Anopheles. Meigen.

„ 2. Myzomyia. Blanchard.

„ 3. Cydoleppteron. Theobald.

„ 4. Stethomyia. Theobald.

„ 5. Pyretophorus. Blanchard.

„ 6. Arribahagia, Nov. gen.

„ 7. Myzorhynchus. Blanchard.

,, 8. Nyssorhynckus. Blanchard.
„ 9. Cellia. Theobald.

. ,, 10. Aldrichia Theobald.

,, 11 Christia. Theobald.

The characters upon which these new genera are founded may
be tabulated thus :—

SUB-FAMILY ANOPHELINA.

Thorax and abdo-
men with hair-
like curved scales.

Thorax with narrow
curved .scales;
abdomen hairy.

Prothoracic lobes
simple ; no flat
head scales.

Prothoracic lobes
mammilated : me-
dian flat scales.

Wing scales lanceolate... Anopheles.

Wing scales mostly long

and narrow ... Myzomyia.

Wing scales partly large

and inflated ... Cydoleppteron.

Wing scales lanceolate Stethomyia.

Wing scales small, lan-
ceolate or narrowed . . . Pyretophorus.

Thorax with hair-like curved scales ; some narrow curved ones in
front ; abdomen with apical lateral scale tufts and scaly venter,
no ventral tuft

Arribalzagia.

Thorax with hair-like curved scales ; abdominal scales on venter

only, with a distinct ventral apical tuft; no lateral tufts ... Myzorhynchus.

18]

Thorax and abdo-
men with true
scales.

Some objections to it.

SUB-FAMILY ANOPHELINA.— (contd.)

Abdominal scales as lateral tufts and dorsal
patches of small flat scales ; thoracic
narrow curved or spindle-shaped ... Nyssorhynchus.

Abdomen nearly completely scaled with irre-
gular scales and with lateral tufts ... Cellia.

Abdomen completely scaled with large flat

scales as in Gulex ... Aldrichia.

The Indian species of " anopheles " described by Mr. Theobald

are placed by him in the following of these new genera.

In the genus Anopheles (1) lindesayi, Giles ; (2) gigas, Giles ;

(3) aitkeni, James ; (4) immaculatus, Theobald.
In the genus Myzomyia (1) rossi, Giles ; (2) culicifacies, Giles ;
(3) Ustoni, Listen ; (4) turkhudi, Liston ; (5) leucophyrus,
Donitz ; (6) elegans, James.

In the genus Pyretophorus (1 ) jeyporiensis n. sp.
In the genus Myzorhynchus (1) sinensis, Wiedmann ; (2) nigerri-
mus, Giles; (3) indiensis, Theobald; (4) barbirostris,
Van der Wulp ; (5) minutus, Theobald.

In the genus Nyssorhynchus (1) maculatus, Theobald ; (2) ful-

ginosus, Giles; (3) jamesi, Theobald; (4) theobaldi,

Giles; (5) stephensi, Liston; (6) willmori, James;

(7) maculipalpis, Giles; (8) karwari, James.

In the genus Cellia (1) pulcherrimus, Theobald.

We have given this short account of Mr. Theobald's method of

classifying " anopheles," for purposes of reference rather than because

we agree that it is the best method by which these insects may

be arranged. Omitting any consideration of the result of the

new classification, viz., that if it is adopted it will be necessary

to say that malaria is transmitted not only by mosquitoes of

the genus Anopheles but also by those of the genera Myzomyia,

Pyretophorus, Nyssorhynchus, etc., — for in spite of their new

names the members of these new genera still remain malaria

carriers — we may enumerate some of the more obvious objections

to the method,

1. The fact that the scale structure of one species of "ano-
pheles" (Aldrichia error, Theobald) is apparently similar

Some more objections.

to that of some " culex " mosquitoes, appears to show
that generic distinctions cannot be based upon scale
structure alone.

2. The classification is based in great part on the shape, and

not upon the presence or absence, of scales. Scales of
various shapes are present on different parts of the
thorax, abdomen, and especially the wings of "anopheles,"
and it is a matter of great difficulty to decide in some
instances what form of scale predominates ; nor does
Mr. Theobald give us any indication of what portion of a
wing, for example, should be examined to decide this point.

3. The terms " lanceolate," " long and narrow," " true scales,"

&c., are not sufficiently definite to permit of such scales
being easily distinguished from one another — except
perhaps by Mr. Theobald himself. It is obvious that
the distinction between " hair-like curved scales " and
" narrow curved scales " is not great, and also that it
would be difficult to decide whether the abdomen is
" hairy," or whether it is covered with " hair-like scales"
which apparently resemble hairs so closely that they
cannot be termed " true scales." As regards the wing
again it would certainly be difficult to decide whether
most of the scales were " lanceolate " or whether they
were " mostly long and narrow " especially as the part
of the wing to be examined is not stated, but on this
decision alone depends the distinction between the
genera Anopheles and Myzcmyia.

4. One of the objects of classification is to simplify the identi-

fication of species, but the new classification does not aid
this in any way. In practice, it will be found much
easier to determine the specific name of any specimen of
" anopheles " than its generic name according to the
new system.

5. Species which differ widely in their habits and patho-

logical significance (e. g., rossi and culicifacies) are placed
in the same genus, while those which are similar in
these important respects (e. g., listoni and jeyporiensis}
are placed in different genera.

20]

Some more objections.

6. Species of which the eggs and larvae — the characters of

which are at least as important as the shape of the wing
scales in the adult insect— are essentially different (e. g.,
culicifacies and turkhudi) are placed in the same genus,
while those with eggs and larvae of the same type are
placed in different genera.

7. The distinctions between the different genera are not of

equal value, for whereas gigas and rossi, for example,
are placed in different genera because in the one case
the wing scales are " lanceolate," while in the other they
are " mostly long and narrow," the fact that the abdomen
of stephensi is densely covered with scales, while that of
maculatus is, practically speaking, entirely free from them,
is not considered sufficient to warrant these two species
being placed in different genera. The same argument
may be used with reference to willmori and some of the
other species in the genus Nyssorhynchus.

It appears to us, therefore, that while differences in scale struc-
ture are undoubtedly of great value in the distinction of species,
such differences as are present — at any rate among "anopheles" —
are not sufficiently important to be considered of generic value,
and it is for this reason that we have retained the generic term
anopheles for all the species described in this book. In a later
chapter we shall refer to this subject in more detail, and give our
own method of classifying these insects, but before doing so we
must describe the methods by which they may be caught, examined,
and identified.

21

CHAPTER II.

THE COLLECTION, MOUNTING, EXAMINATION AND IDENTIFICATION OF
ANOPHELES MOSQUITOES AND THEIR LARVAE.

recording observations on the habits and life-history
of " anopheles " there has been, until recently, a
tendency to apply the facts deduced from observa-
tions of one species only, to the whole sub-family,
without taking into account the fact that different
species may vary greatly in their habits and life-history. At the
present time, however, it is extremely important to study each
species of " anopheles " separately, and it is desirable, therefore, to
give briefly some methods that have been found successful for the
collection of the adults and larvae, in order that those who are
interested in the subject may find and separate the various species
present in their districts before commencing a study of their habits
and life-history.

The collection of adult Anopheles. — The collection of the so-
called "domestic" species — that is, those species which are never
found far from the neighbourhood of human habitations — is, as a
rule, an easy matter in India provided search for them is made in
the right places. The majority of the known species rest during
the day-time in houses, stables, and sheds, and in such haunts
they may be easily captured by gently placing the open mouth
of a test-tube over them as they rest on the walls or roof. A
slight movement of the tube while it is kept pressed against
the wall or roof will rouse the mosquito and make it fly towards the
closed end of the tube, the mouth of which can then be closed by
insinuating a cotton-wool plug between it and the wall or roof.
Mosquitoes caught in this manner can either be kept in the test-
tubes, or if a large number are required, as for the purpose of
dissection, it is preferable to transfer them from the test-tubes into
a large bottle with a narrow neck (such as an empty white glass

22]

The Collection of Anopheles Mosquitoes

wine bottle), so that the test-tubes can be used again. In this way
if " anopheles " are at all plentiful, fifty or sixty can be caught in a
very short time.

But before commencing the search for adult mosquitoes of this
kind it is advisable to carefully select a suitable place. A native
village with breeding places near (such as a stream, or canal, or
ponds) should be chosen if possible. In such a village there will
probably be several old unoccupied huts and sheds, and it is in these
a good catch is most likely to be made. It is almost useless to
search in a new house with whitened walls. The best place of all
is in old unoccupied house with smoke-blackened thatched roof and
mud walls. It is better to look first in an unoccupied house, because
the smoke from the wood fires in houses where people are living,
drives most of the mosquitoes out during the day-time into the
nearest empty house or shed. Cowsheds in the middle of a village,
native carpenters' shops, wood sheds, and the barracks of native
soldiers, are also good places in which, to search for " anopheles "
mosquitoes.

In houses with high roofs it may be necessary to mount on a
ladder in order to very carefully examine each section of the thatch.
The darker corners, the angles between the rafters and the thatch,
and the cobwebs hanging from the roof, are favourite resting
places of these mosquitoes. The commoner species, such as A.
rossi, are usually seen at once, because they are light-coloured and
large and stand out against the black background of sootlike little
white thorns hanging from the roof, but the smaller darker coloured
species are difficult to see. A. culicifacies, for example, hides most
successfully in holes and corners of the roof, and in many places it
would be possible to catch several hundred specimens of A. rossi
in the time that it would take to catch fifteen or twenty specimens
of this species. A difficulty also arises in collecting specimens of
this very important species, from the fact that, as it does not
assume the characteristic attitude of the majority of " anopheles "
mosquitoes when resting on a wall or roof, it is very liable to be
mistaken for a small brown "culex." For this reason, as well as for
the reason that species of " anopheles " occur in India, the wings of
which are entirely unspotted, it is advisable, in rooms which are
badly lighted, to catch all the mosquitoes that are seen, without

[23

Favorite haunts of the adults.

taking note at the time whether they are " culex " or " anopheles."
As each mosquito is caught, the tube containing it can be taken to
the light, and the mosquito carefully examined before transferring
it to the large bottle.

In occupied houses and in barracks and hospitals, " anopheles "
are more likely to be found on dark-coloured clothes hanging in the
corners of the rooms or in the cupboards, or resting on the under-
surface of the shelves which usually surround the walls of barrack-
rooms. Saddles and harness of all kinds are also favorite resting
places of this kind of mosquito, and in the harness rooms of the
cavalry regiments at Mian Mir as many as twenty or thirty can
often be seen resting on the under-surface of each saddle hanging
up in the rooms.

In stables and out-houses of Indian villages, it is usual for the
natives to store a number of dried mud and straw cakes which are
used for repairing their houses, and if one of these heaps of mud
cakes is kicked over, a large number of "anopheles" will often fly
out. In such a case as this a muslin net will be found very useful for
catching the mosquitoes as they fly out. With one sweep of the
net it is often possible to catch ten or twelve A. culicifacies after
disturbing one of these heaps, when it may be difficult to find any
specimens of this species resting on the walls or roofs of the houses.

In addition to collecting the species which are commonly found
in the neighbourhood of habitations, it is very important to search
for those species which are seldom or never found in houses and
which may be termed " wild " species of " anopheles. " They may
sometimes be caught by the following method : — On a night when
there is little or no wind a white sheet is hung near the ground
under some trees, and a lighted lamp is placed on the ground in
front of the sheet. The mosquitoes are attracted by the lamp and
alight on the white sheet, when they may be caught by placing a
test-tube over them in the usual way. Another plan is to erect a
tent in the jungle or other place where we wish to search for these
mosquitoes. After a day or two several will almost certainly be
found in the corners of the tent and beneath the folds of its
hangings. This method is of great service in villages where the
inhabitants are unwilling to permit search being made in their
houses.

24]

The Collection of Larva

The collection of larva. — The collection of adult mosquitoes
should be supplemented by collecting the larvas, which may be kept
and bred out into adult mosquitoes.

On account of the fact that pools and streams frequently
contain " anopheles " larvae when none can be seen on the surface
of the water, the method of " dipping " should always be employed
for their collection.

One of the best things with which to dip for larvae is a large
tin mug, but a calico or muslin net with a long handle is of advan-
tage for fishing in the middle of a pool or stream. Besides the
dipper and net, a number of wide-mouthed bottles should be taken
when going out to search for larvse. When any collection of water
is reached, the dipper should be scooped along the surface, under
the grass or weed at the edge, and brought out full of water. If
any larvae have been caught they can easily be recognised in the
dipper when they rise to the surface, and they should then be
transferred with some of the water and weed into one of the wide-
mouthed bottles. In running streams care should be taken to dip
several times in the eddies and beneath the grass overhanging the
edge of the water, as in such places larvae are most likely to be found.
The larvae from different breeding places should be kept in separate
bottles, in order that when they have been bred out and identified,
the character of the breeding places of the different species will be
known.

In searching for " anopheles " larvae, it is important to note
that no collection of water should be passed over without careful
examination, for it often happens that the most unlikely-looking
collection of water will yield many larvae.

Each wide-mouthed bottle should be half-filled with water
from the pool or stream in which the larvas were taken. In some
cases, — especially in the case of larvae collected from running
streams — it is necessary to change the water daily if healthy larvae
are to be reared. The mouths of the bottles are covered with fine
muslin or mosquito netting, and allowed to stand in a warm place,
but bright sunlight should be avoided if possible. Each day the
adult mosquitoes which have developed from the larvae may be
transferred to a clean dry bottle, in which they should be allowed
to remain alive for one or two hours in order that they may attain

[25

How to Mount Mosquitoes

their proper colour and size. After this period they may be killed
and mounted for examination.

The mounting q/ Anopheles. — In making a collection of
mosquitoes it is desirable to get as perfect specimens as possible,
and for this reason the " anopheles " which have been caught or
bred from larvae, should not be kept alive in the bottles longer than
is necessary, lest by rubbing their wings against the glass when
flying about, some of the scales may be rubbed off. The insects are
best killed by dropping a few drops of chloroform on to the muslin
covering the mouth of the bottle in which they are confined. Tobacco
smoke should not be used for killing mosquitoes as it alters the
colour of the markings. Immediately after the insects are dead,
they should be turned out on to a clean sheet of cork carpet. If
left too long exposed to the fumes of chloroform, the legs become
fixed in awkward positions and brittle. Great care should be taken
not to touch the insects with the fingers or some of the fine scales
will be rubbed off, and if it is necessary to move any of them, a fine
needle or pin should be used for the purpose. In order to mount
mosquitoes the following articles are necessary : —

4*v (1) Fine entomological

silver pins (No. 20 size).

(2) A pair of forceps for
holding the pins.

(3) Common pins.

(4) Small discs of thin
cardboard such as are used
for gun wads, the size of a
20-bore gun.

(5) A wooden box, in
the floor of which is fixed a
layer of cork carpet or pith,
into which the pins can be
inserted and firmly fixed.

A card-disc should be
taken, and all the data con-
cerning the specimen to be

Fig.- 4 (After Theobald.) ° \

mounted, should be written
upon it. Then one of the No. 20 pins should be firmly grasped

26]

\

How to preserve them

near its point with the forceps and thrust through the centre of the
disc until about half its length projects through it. The mosquito,
which is lying dead on the sheet of cork, should be turned on to its
back with the aid of a pin, and, holding the head of the pin carrying
the cardboard disc between the thumb and first finger of the right
hand, the point of the pin is thrust into the thorax of the mosquito
between the points of origin of the legs, and pressed onwards until it
emerges through the dorsal surface of the thorax. When the pin and
disc are lifted off the cork and inverted, the mosquito will be in its
natural position, right side upwards. The wings and legs may now
be carefully arranged with the aid of a fine pin, but this is often
unnecessary, and if all the parts can be seen moderately well, it is
best not to touch them, as even the most careful manipulation will
rub off some of the scales and hairs. An ordinary pin is thrust
through the card disc near its margin for the purpose of attaching
it to the cork in the floor of the entomological box. (See Fig. 4).

In India, mosquitoes very quickly become
covered with mould, and in order to prevent
this, and to preserve them properly, they
are best kept in the small glass tubes shown
in fig. 5.

A flat cork (D) fitting very tightly is first
pressed into the tube to its end. On this
cork a small muslin bag (C) containing
naphthalene is placed. This is kept in posi-
tion by means of a cardboard disc perforated
with holes (B) which is fastened firmly by
pins to the cork in the bottom of the tube.
The disc carrying the mosquito (A) is pinned
to the cork which closes the mouth of the
By this method mosquitoes may be

tube.

preserved in good condition for a long time,

and if the tubes are well packed in a tin box Fis- 5<

with cotton-wool, they may be sent through

the post with safety.

In addition to mounting male and female specimens of each
species in the manner just described, it is necessary to have certain
parts of each species mounted separately on glass slides. These

[27

How to examine and describe an Anopheles

parts are the wings, the male genitalia, and the male and female
ungues (especially the ungues of the fore leg in the male).

The wings are best mounted dry beneath a thin coverslip, which
may be kept in place by strips of gummed paper or by ringing it
with thick Canada balsam. The wings should, of course, be mounted
perfectly flat.

The male genital ia and the ungues should be mounted beneath
thin coverslips in xylol balsam.

The examination of adult Anopheles. — For the examination of
adult mosquitoes a low power microscope (half or two-thirds inch
objective) is necessary. The mosquito
to be examined (which has already
been mounted on a card-disc in the
usual manner) is fixed by a pin thrust
through the edge of the card-disc to a
flat cork about an inch square. This
piece of cork carrying the mosquito
is placed on the microscope stage, and
can be moved about at will (fig. 6).
The angle at which the pin is fixed in
the cork should be such that the part
of the mosquito which is being exa-
mined is always as nearly as possible
parallel to the microscope stage.

In order to be in a position to give a
complete description of a mosquito, it
is best to begin with an examination
of the palpi, proboscis, arid antennas, and to work backwards, noting
every marking and character that presents itself. The position of
the disc carrying the mosquito will of course have to be frequently
altered by removing the pin from the cork and readjusting it at a
different angle. The character of the antennaa will at once show
whether the mosquito is a male or female, and the length and
characters of the palpi whether it is a "culex" or an "anopheles."
(See PI. Ill, figs. 1 to 4.) In the examination of the palpi it will also
be noted whether they are uniformly coloured or whether they are
encircled with white bands, and the number, relative size, and posi-
tion of any such bands will be described. (See coloured plates.) In

28]

6.

The head, thorax, abdomen, and wings

addition to definite bands a few white scaled patches may be present
on one or more segments of the palpi as in A. maculipalpis and A.
stephensi. Passing on to the examination of the head, the characters
of the different groups of scales will be noted, and in particular the
characters of the upright forked scales can be readily made out. In
most species of " anopheles " a prominent tuft of white hairs project-
ing forwards from the anterior end of the head will be seen. The
thorax will next be examined, and on its dorsal surface a large
number of scales and a few hairs will probably be present. The
characters of these scales and hairs are of importance in identifica-
tion and should be carefully described. Passing on towards the
abdomen, the scutellum will be examined. In addition to the long
bristles which will be readily seen attached to its border, the scutel-
lum sometimes carries a few scales similar to those on the thorax.
The bare horse-shoe shaped metanotum will next be seen, and then
the halteres, the knobs of which are sometimes clothed with numer-
ous small silvery scales.

The examination of the abdomen is of great importance. In
many species, although the abdomen is thickly covered with long
hairs, no scales are present. In some species, however, it will be
seen that in addition to the hairs covering the majority of the
segments, a few golden-brown or dark-coloured scales can be made
out, especially on the ventral surface of the last one or two segments
only. In other species, again, it will be at once seen that the whole
surface of the abdomen is thickly set with white or golden brown
scales, which in some species are very broad (as in A. pulcherrimus),
and in others more or less spindle -shaped (as in A. stephensi). It
will readily be recognised that the presence or absence and the
character of these abdominal scales is a very important aid in the
determination of species.

The wings and legs will next be examined.

The most useful way of describing the wing markings is by
means of a diagrammatic drawing giving the number and relative
size and position of the different dark and light-scaled areas on each
vein. The detailed shape of the wing scales, which is a point of
some importance, and the relative position of the transverse veins
must be noted by a separate examination of a wing mounted under
a cover -glass.

[29

The identification of species

The legs should be examined in order, and a careful description
of the markings on each leg, commencing with those on the femur
and ending with those of the fifth tarsal segment, made. It will be
seen that in many species complete bands of white scales encircle
the legs near the joints, and the position and characters of these
bands should be noted. In addition, small patches of white scales,
not amounting to complete bands, will be found in some species on
many of the segments of the legs ("speckling"), and in some
species one or more of the terminal tarsal segments of the hind legs
will be found to be white-scaled in their whole length.

The description will be completed by an examination of the
male genitalia and of the ungues (special note being taken of the
characters of the fore ungues in the male), these structures being
separately mounted on slides for this purpose.

The Identification of adult Anopheles. — The identification of
most of the Indian species of " anopheles " is not by any means a
difficult matter if one sets about the task in a systematic way.
We have just indicated the parts of a mosquito which must be
examined in detail if it is desired to give a complete description of
the insect, but for identification it is not, as a rule, necessary to
examine all these structures minutely, and many of the Indian
species can be readily identified by an examination with a hand-
lens or even with the naked eye. The first requisite for the task
of identification is the possession of a synoptic table such as the
one given on page 32. This table is founded chiefly upon the
markings of the palpi, which afford a satisfactory basis on
which the Indian species may be divided, for purposes of identifica-
tion, into a number of groups, such as "those with unhanded palpi,"
*' those with three white bands on the palpi," &c. These groups
may be subdivided into smaller ones by the markings on the legs,
as, for example, among the " three-banded palpi " group a sub-group
containing the species in which one or more of the terminal segments
of the hind legs are pure white, another sub-group containing the
species in which, though none of the hind tarsal segments are pure
white in their whole length, there are distinct white bands at the
tarsal joints, and a third sub-group containing the species in which
the legs are uniformly coloured without any distinct bands. Each
of these sub-groups will be found to contain only a few species,

30]

Palp markings as a basis for identification

which may be easily distinguished from one another by other
characteristic markings. When the probable name of the mosquito
we are dealing with has been found out by means of the table the
full description of the mosquito of this name may be turned up (in
Part II of this monograph), and we can ascertain by a more
thorough examination of all the markings, scale structure, &c.,
whether we have identified the insect correctly.

In selecting the palp markings as the basis of the table of
Indian species, we have been guided by the facts that they are less
variable than the markings on the legs or wings, and that, whether
as a result of coincidence or not, such an arrangement of the
Indian species brings together into the same groups the species of
which the habits and pathological significance are very similar. It
should be noted that the markings of male mosquitoes vary so
much that it is not advisable to use them for the identification of
species and female specimens only should be employed.

A few examples will serve to illustrate the method of using
the table.

Example I. — A MOUNTED MOSQUITO FOR IDENTIFICATION.

Antennae. — With short, inconspicuous hairs at the joints
(Plate III, Figs. 2 & 4), showing that the mosquito is a female.

Palpi. — As long as the proboscis (Plate III, Fig. 4) showing
that it is an " anopheles."

Wings. — Spotted with dark and light scaled areas. The
mosquito therefore comes under group I.

Palpi. — With three white bands or rings, viz., one broad ring
including the tips (which are therefore white) and two narrower ones.

It therefore comes under the group C, sub-group 2.

Legs. — None of the tarsal segments of the hind legs are white
in their whole length, but there are distinct white bands at the
tarsal joints (sub-group 6).

The mosquito is therefore A. rossi or A. stephensi. The
femora and tibiae are not speckled with white patches, and the
abdomen is not covered with scales.

Diagnosis. — A. rossi.

Confirm by comparison of the wing and other markings with the
coloured plate of A. rossi and with the description of that mosquito.

[31

Table for the Identification of Anopheles

I WINGS SPOTTED.

A.— Palpi unbanded.

1. A. lindesayi (Giles) ... ... Wings with one large white spot near the apex.

Femora of hind legs with a broad white band.

2. A. gigas (Giles) ... ... ... A large species with three creamy white spots on the

costa.

3. A. barbirostrit (Van der wulp) ... A very large species with black densely-scaled palpi.

Costa with two small light spots.

B.— Palpi with four white bands.

1.— LEGS BANDED AND FEMORA AND TIBI.E SPECKLED WITH WHITE SPOTS.

4. A. pulcherrimus (Theobald) ... The third, fourth, and fifth hind tarsal segments

white. Abdomen covered with scales.

5. A. elegant (James) ... ... None of the hind tarsal segments pure white. No

scales on abdomen. A very broad band at the
tibio-metatarsal joint of hind legs.

6. A. punctulatus (Donitz) ... ... No broad white band at tibio-raetatarsal joint.

2.— LEGS BANDED BUT FEMORA AND TIBIAE NOT SPECKLED.

7. A. OTrt«n*w (Wiedmann) and its allied

species A. nigerrimus (Giles), &c. None of the hind tarsal segments pure white.

8. A. karwari (James) ... ... The fifth tarsal segment of the hind legs pure white.

C — Palpi with three white bauds.

1.— TIPS OF PALPI BLACK.

9. A. turkhudi (Listen) ... ... None of the hind tarsal segments white.

10. A. nagpori (James) ... ... The fourth and fifth hind tarsal segments pure white.

2.— TIPS OF PALPI WHITE.

(a) Tarsal joints banded and one or more of the hind tarsal segments white.

11. A. fuliginosus (Giles) ... ... The third, fourth and fifth hind tarsal segments pure

white. Femora and tibiae not speckled.

12. A. jamesi (Theobald) ... ... As No. 11, but femora and tibiae speckled.

13. A. maculipalpis (Giles) ... ... As No. 12, but palpi have two broad and one narrow

bands instead of one broad and two narrow ones,
and the palpi as well as the legs are speckled.

14. A. theobaldi (Giles) ... ... Legs speckled, but only the 4th and 5th hind tarsal

segments are pure white.

15. A. maeulatus (Theobald) ... ... Only the fifth hind tarsal segment is pure white.

16. A. willmori (James) ... ... Differs from No. 15, in having many scales on the

abdomen.
(6) Tarsal joints banded, but none of the hind tarsal segments white.

17. A. rosti (Giles) ... ... ... Femora and tibiae not speckled.

18. A. stephensi (Listen) ... ... Femora and tibia speckled. Abdomen covered with

scales,
(c) Legs uniformly coloured without distinct bands or white segments.

19. A. listoni (Listen) ... ... The third long vein of wing white scaled ; the sixth

mostly dark scaled. Six white patches on wing
fringe.

20. A. jeyporiensis (James) ... ... The third long vein of wing white scaled ; the sixth

mostly light scaled. Seven white patches on wing
fringe.

21. A. culicifacies (Giles) ... ... The third long vein of wing black scaled. Two white

patches on wing fringe.

II.— WINGS UNSPOTTED.

A.— Palpi unbanded.

22. A. aitkeni (James).

23. A. culiciformit (Listen).

B Palpi distinctly lighter coloured in their outer third.

24. A. immaculatus (Theobald).

32]

Examples in Identification.

Example II. — A FEMALE " ANOPHELES."

Wings. — Spotted.

Palpi. — With three white rings, the outermost of which includes
the tips. The two outer rings are broad and the third narrow.
In addition to the three complete rings there are one or two small
patches of white scales which do not amount to a complete ring or
band, on the upper surface of each palpus ; i.e., the palpi are marked
with three bands and are " speckled " in addition.

The mosquito comes under the group C, sub-group 2.

Legs. — The 3rd, 4th, and 5th tarsal segments of the hind legs
are pure white in their whole length.

(NOTE. — It is sometimes rather difficult to determine by the naked eye or with
a hand-lens the exact number of tarsal segments which are pure white, for the 5th
segment is very short. The matter can easily be decided by an examination under
a low power of the microscope.)

The mosquito is therefore either A. fuliginosus, A. jamesi,
or A. maculipalpis.

The femora and tibiae are brilliantly speckled with white scales.

This excludes A. fuliginosus, and the speckling of the palpi
together with the fact that there are two broad and one narrow
bands 011 the palpi, instead of one broad and two narrow ones,
excludes A. jamesi, so that the diagnosis is A. maculipalpis.

Confirm as for example I.

Example III. — A FEMALE " ANOPHELES. "

Wings. — Spotted.

Palpi. — With three white rings, the outermost of which
includes the tips.

As in the other examples, the mosquito comes under the group
C, sub-group 2.

Legs. — Uniformly coloured without distinct bands at the tarsal
joints.

(NOTE. — In several of the unbanded legged species the segments may be lighter
coloured at the tarsal joints, and in A, jeyporiensis this may be so marked as to form
faint whitish spots. It will readily be recognised, however, that this lighter coloura-
tion does not amount to the fairly broad " distinct white bands," about the presence
or absence of which there can be no doubt even with the naked eye.)

The mosquito is either A. listoni, A. culictfacies, or A. jey-
poriensis.

[33

Doubtful Species.

Separate by careful examination of the wing markings. ( See
coloured plates and descriptions.)

The following, which are described as Indian species by Mr.
Theobald, are not included in the synoptic table : —

(1.) Anopheles (Myzomyia) leptomeres.
(2 ) ,, (Myzorhynchus) vanus.

(3.) „ „ minutus.

(4.) „ (Aldrichia) error.

Some remarks regarding these species will be found in Part II.

The examinat-on and identification oflarvce. — The larvae of
mosquitoes may be examined when alive or when killed and mounted
on slides. In order to examine a larva when it is alive it is caught
in a small spoon — care being taken not to injure it — and transferred
with a drop of water on to a glass slide. A cover glass is then
dropped very gently on to it. This has the effect of preventing
the larva from continually wriggling out of the field of the
microscope, and, if carefully done, it does not break any of the
larval hairs or injure it in any way.

Permanent specimens of larvae may be obtained either by
mounting them simply in a solution of formalin in hollow ground
glass slides, applying a cover glass and ringing it with thick Canada
balsam, or by the following more permanent method, first
recommended by Dr. Christophers.

(a) Kill the larva by immersing it in strong formalin solution,
and allow it to remain in this solution for at least
twelve hours.

(6) Immerse the larva after treatment in the formalin solution,
in absolute alcohol for fifteen minutes.

(c) Immerse it in oil of cloves.

(d) Clear with xylol and mount on an ordinary flat slide under

a cover glass in xylol balsam.

During the above process very great care must be taken to
handle the larvae gently so as not to break any of the finer hairs.
They are best removed from one dish to another by lifting them
up very gently on the edge of a piece of stiff paper.

Another plan, which shows the palmate hairs and some other
characters of the larvae exceedingly well, consists in mounting the

34]

A.

PLATE

B.

8.

PLATE IV. The larva of A. macuiipatpig ; .4.— General view of the full grown larva; B. — One of the palmate hairs magnified; C.— The frontal
hairs (Median and External) of the right side, magnified.

The Examination of Larvce.

cast larval skins. These skins are very transparent, but they can
be seen without difficulty floating near the surface of the vessel of
water in which the larvae are kept. Dr. Cogill recommends that
the larval skin, after having been transferred to a glass slide, should
be allowed to dry thoroughly and then mounted in thin Canada
balsam beneath a cover glass.

It is of great advantage to be able to identify the different
species of " anopheles " by an examination of their larvae alone,
without the necessity of breeding out the larvae into adults. Grassi
was the first to show that this could be done for some of the
Italian species, and recent work by the members of the Royal
Society's Malaria Commission in India has shown that the majority
of the known Indian species can also be differentiated in the larval
stage of their existence.

The structures by which the larvae of different species of
" anopheles " may be identified are as follow : —

(L) The Frontal or Clypeal hairs (PL IV, A & C).— These
are four fine hairs which project from the dorsal surface of the
anterior end of the head. They may be called the external and
the median frontal hairs. The external hairs are placed one at
each corner of the dorsal chitinous end of the head, and exactly
overhang the prominent so-called whorl organs or " shaving
brushes." When the whorl organs are pushed out, the external
(corner) hairs are difficult to see, but when the whorl organs are
drawn in, they stand out prominently. The median hairs arise
close together near the middle line and project forward in front of
the head. They are easily seen under a ^ or ^ inch objective.

A very important difference between the larvae of different
species depends upon the fact that the characters of these external
and median frontal hairs differ in different species. The details of these
differences are given under the descriptions of the several species.

(2) The Palmate hairs (PL IV, A & B).— If the dorsal
surface of the abdomen of an " anopheles " larva is examined
under the microscope, a pair of little fan -shaped organs will be
seen on the majority of the segments. These are the so-called
"Palmate hairs." Each consists of a short stalk surmounted by a
bundle of about 15 to 18 hairs which are arranged round the stalk
like the petals of a flower. When the larva comes to the surface

[35

The Identification of Larva.

these leaflets spread out and form a series of little cup-shaped organs
which serve to keep the larva floating in the horizontal position.
Both the number of the palmate hairs and the shape of each leaflet
differ in different species of " anopheles," so that in this fact we have
a second means of distinguishing the larvae of different species.

(3) The Antenna (PI. IV, A.) — These structures are very
easily recognised, and in the majority of Indian species they differ
but little. A very small hair should be noted on the outer side of
the antenna at about the junction of its middle and lower third in
the majority of the larvae.

The larvae of two of the Indian species of "anopheles," however
are readily distinguished from those of any other species by the
presence of a stout branching hair on the inner side of each
antenna, quite distinct from the small external hair referred to
above. The characters of this large branching hair are shown in the
diagram of the larva of A. barbirostris (Plate V, Fig. 1, A and D).

(4) The pattern of the head markings. — Although the pattern
on the dorsal surface of the head of " anopheles" larvae is
formed by dots of pigment only, and is therefore liable to
considerable variation, yet in some species the head pattern is
sufficiently constant to be of assistance in the identification of
larvae. The inverted triangular area enclosing four dots of pig-
ment on the dorsal surface of the head of the larva of A. rossi,
for example, is very characteristic (PI. VI, Fig. 1, A), as is
also the complete absence of any pattern on the head of the
larvae of A . stephensi (PL VI, Fig. 2, A). The usual markings on
the heads of these and other larvae are given in the diagrams.

(5) The Basal hair. — We have already described in Chapter I
the position of this hair. Its shape and character are particularly
remarkable in the larvae of A. culiciformis and at once serve to
differentiate the larvae of this species from all others.

(6) The Posterior hair.—Ln some larvae, as we have already

mentioned, two hairs arise from the clypeus behind and between

the frontal hairs. In the larvae of A. turkhudi (PI. VIII, Fig. 2 )

these hairs are unbranched and very long. In the larvae of A.

jeyporiensis (PI. VII, Fig. 2) they are short but branched.

It should be noted that in the identification of any particu-
lar larva, too much stress should not be laid on any one of the

36]

Table of the Larva of Indian Anopheles.

above structures alone, but that a careful consideration of the
characters of all the structures taken together will yield the most
accurate results. This is necessary because, as Dr. Cogill has
recently shown, the characters of the frontal hairs may occasionally
vary even among a series of larvas from the same batch of eggs.

As an aid to the identification of the larvae of some of the
Indian "anopheles," we may arrange those of which the characters
are known in the following table, which is a modification of that
given by Stephens and Christophers : —

I.— ANTENIM/E WITH A LARGE BRANCHED HAIR

A.— With simple unbranched frontal hairs.

1. A. lindesayi.

B.— With branched frontal hairs.

2. A. barbirostris ;.. ... ... Median frontal hairs unbranched. The branches of

the external frontal hairs arise from the main stem
and from other branches.

3. A. nigerrimus ... ... ... Median frontal hairs unbranched. The branches of

the external frontal hair all arise from the main
stem.

II.-ANTENN/E WITHOUT A LARGE
BRANCHED HAIR.

A.— With fully developed palmate hairs on the thorax.

(a) With simple unbranched frontal hairs.

4. A. culicifacies ... ... ... The filaments of the palmate hair leaflets rather long.

5. A. listoni ... ... ... Palmate hairs very large and distinct on the thorax

and abdominal segments. Filaments of leaflets
shorter. Characteristic head pattern.

6. A. culiciformis ... ... ... Basal hair characteristic. Median frontal hairs

long. Leaflets of palmate hairs taper to a point.

(b) With branched frontal hairs.

7. A. jeyporiensis ... ... ... Two small branched posterior hairs in addition to

the frontal hairs. Palmate hairs very large and
distinct. Filaments of leaflets short.
8 A. maculipalpis .,., ... ... No posterior hair. Filaments of palmate hair

leaflets rather long.

B.— Without fully developed palmate hairs on the thorax.

(a) With simple unbranched frontal hairs.

9. A. rossi ... ... ... ... Characteristic head pattern. Fully developed pal-

mate hairs on the 3rd to the 7th segments of
abdomen. Filaments of leaflets very long.

10. A. stephensi ... ... ... No head pattern. Filaments of palmate hair leaf-

lets shorter.

11. A. theobaldi ... ... ... Filaments of palmate hair leaflets very short and

blunt.

12. A. maculatus ... ... ... Filaments short but sharp pointed.

13. A. elegans ... ... ... Leaflets of palmate hairs taper to a point; no

distinct filaments.

14. A. turkhudi ... ... ... Two very long unbranched posterior hairs in addi-

tion to the frontal hairs. Fully developed palmate
hairs on the fourth, fifth and sixth abdominal seg-
ments only.

15. A. karwari.

(b) With branched frontal hairs.

16. A. fuliginosus ... ... ... Frontal hairs very much branched.

17. A. pulcherrimus ... ... ... Frontal hairs only slightly branched or frayed.

18. A. aitkeni ... ... ... External frontal hairs unbranched, median forked.

[37

How to collect and examine the eggs.

The examination and identification of eggs. — In order to obtain
eggs of " anopheles" it is necessary to preserve some female mos-
quitoes of this kind that have been caught in a native village, until
they have deposited their eggs. The best method of keeping
mosquitoes alive for this purpose is that recommended by
Drs. Stephens and Christophers. A glass "chutney" or " pickle" jar
with a wide mouth and a hollow glass stopper is obtained, and after
it has been thoroughly cleaned and dried a piece of cardboard is
placed in it of such a size that after being forced into the jar it
remains firmly fixed (Fig. 7). The stopper is
filled nearly to the brim with water, and a thin
piece of cork covered with white paper is put to
float in it. The mosquitoes that have been caught
(both males and females) are transferred from the
collecting tubes into the jar, which is then placed
upside down upon the stopper in a dark cupboard.
If mosquitoes from a village are used, it will usually
be found that even after one night some of them
will have deposited their eggs. Some of the
eggs will almost always be found on the white
paper, which can then be removed and placed
on the microscope stage, the eggs being examined
by reflected light with a half or two-thirds inch objective.

Great care should, of course, be taken that all the mosquitoes
in the jar are of the same species, for, if more than one kind is
introduced, it will be impossible to tell to which species the eggs
belong.

The points to which attention should be directed in the examin-
ation of an " anopheles" egg are :

(1) The upper surface. — The width of the upper surface
should be carefully measured, and it should be especially noted
whether the floats almost touch each other on this surface, or
whether their inner edges are wide apart.

(2 ) The floats. — The character, size and extent of the floats
should be noted, and it should especially be seen whether their
inner edges encroach on the upper surface of the egg, or whether
the floats are inserted laterally so that their inner edges are wide
apart on the dorsum of the egg.

38]

Fig. 7.

(after Stephens and
Christophers.)

Characters of Anopheles eggs.

(3) The rim or frill. — It should be noted whether the rim is
wide or narrow and whether the floats appear to arise from it, or
whether they arise behind it, in which case it would be continued
uninterruptedly round the upper surface of the egg.

(4) The lower surface. — It should be noted whether the lower
surface is smooth and uniformly coloured, or whether it is marked
with silvery lines dividing it into a number of polygonal areas.

Fig. 8. (After Stephens and Christophers.

1, A. culicifaeies ; 2, A. pulcherrimus ; 3, A. rossi ; 4, A. stephensi : 5, A. turkhudi ;
6, A. maculipalpis.

The following types of " anopheles" ova have been described
by Drs. Stephens and Christophers : —

Type 1. — Ova having the upper surface very narrow, the rim or

frill being continued uninterruptedly round this surface

and the lateral floats not touching its margins (Fig. 8, 1).

Some species with ova of this type are : — A culicifacies, A.

listoni, A. barbirostris, A. nigerrimus.

Type 2. — Ova having a more or less broad upper surface with
the lateral floats touching its margins and apparently
arising from the frill (Fig. 8, 2, 3, 4, 6.)

[39

Types of Ova.

Some species with ova of this type are :— A. rossi, A. pul-
cherrimus, A. juliginosus, A. stephensi.

Type 3. — Ova with no floats and with the upper surface rudi-
mentary (Fig. 8, 5.)

Only one species, viz., A. turkhudi, is at present known to have
ova of this type.

Further details regarding the ova of different species will be
found in Part II.

40]

• j /^.--.- '{"j*"''

--

T S.

\pTKf; ni

•*t»-iir. a ad throughout tht-
«*w *t*ii<llE<pi#iy prevalent. To a&cirtjui*, »vith any
• ••-: .«>f4Mrp, (he oft«ct diwtribution of each species that
» C**k requiring the nttentiori ni niaux*
^<r . cotwhiiTAbU1 period of liine, and ar })resenl
• -I ^ * . in a general way, th*

-.'< * r^o t-{ if«- !:••«. i*rr known species. This we
•>«:. rt»- riAp which accompanies .thi«

,,>f cb"«r w'i->^ work or pleasure takes them
.,i-.^«r.M»r«<i 6rf»m ihw point of view, will fill in
*««* >*i pf-«-*«'ftt oacapyin^ <*> Urge a f»art of the outline.
<.::.^«. it would seem that many species
*% .{. b'jrbiroslris, A. niyerrimus> and A.
••• length and breadth of the country.
< '-i-fMta^ and A. maculipalyris, have beer*
tb and as far south as Travancore,
i the intervening territories, pro-
•d for in those parts by

\ at least, of

•

-A. m«
, A. (•'•

A. trosst xx

A. fULIGINOSUS OO

A. MACULtPAlPIS ••

A. THEOBALOI .. _ _

A. PULCHZRRIMLia, ft

A. CULICIFACIES

A. LISTONI

CHAPTER III.

THE HABITS OF INDIAN ANOPHELES.

Distribution and prevalence.

may perhaps be owing to the fact that " anopheles''
mosquitoes have been more closely studied in India
than in any other tropical region, that the number
of species recorded from this country is greater,
and the known distribution of individual species
appears to be wider, than in any other part of the world. Indeed,
there is as yet no trustworthy record of the absence of " anopheles"
from any part of India, and they have been shown to be present
more or less abundantly wherever careful search for them has been
made. Even in places at a height above the sea-level of between
6,000 and 7,000 feet they frequently occur, and throughout the
plains they are exceedingly prevalent. To ascertain, with any
approach to accuracy, the exact distribution of each species that
occurs in India, would be a task requiring the attention of many
trained observers for a considerable period of time, and at present
it is impossible to do more than indicate, in a general way, the
partial distribution of some of the better known species. This we
have attempted to do on the outline map which accompanies this
chapter, in the hope that those whose work or pleasure takes them
to parts as yet unexplored from this point of view, will fill in
the bare spaces at present occupying so large a part of the outline.
So far as our knowledge goes, it would seem that many species
such as A. rossi, A.fuliginosus, A. barbirostris, A. nigerrimus, and A.
culicifacies, occur throughout the length and breadth of the country.
Others, such as A. pulcherrimus, and A. maculipalpis, have been
found as far north as the Punjab and as far south as Travancore,
but have not been recorded from the intervening territories, pro-
bably because they have not been searched for in those parts by
competent observers. It is also known that some, at least, of the
species occur in other countries as well as in India — A. maculipalpis,
for example, which is a common African species, A. barbirostris,

[41

General and local distribution.

which occurs in Java, the Malay Archipelago, Old Calabar, &c. , and
A. maculatus, which occurs in China. The group of Indian species,
including A. listoni and A. culicifacies, is also very near, if not iden-
tical with, the African group, including A. funestus and its allies,
and the unspotted winged species A. aitkeni is a near neighbour
of the European species A. bifurcatus, and the Algerian species
A. algeriensis. It would seem, therefore, that many of the Indian
species have a wide distribution in nature. But a distinction must
be made between the general distribution of a species and its dis-
tribution in the particular countries where it occurs. There seems
no reason to doubt that some "anopheles," such as A. rossi, do not
habitually act as carriers of malaria in nature. To whatever cause
this is due — whether to the fact that such species have become
immune to the malaria parasite, or because they habitually feed on
the blood of domestic animals rather than on that of man — it is the
chief reason why a knowledge of the local distribution of individual
species is so important. Although the geographical distribution
of a species may be wide, its local distribution may be very limited.
A. listoni, for example, though it has been found in India as far
north as the foot of the Himalayas and as far south as Goa in the
Bombay Presidency, is quite unknown in the Punjab. A. rossi and
A. stephensi, also, though they are very common in Calcutta, are
very rare or absent in many parts of the Duars, which is only a com-
paratively short distance away. A. jeyporiensis, again, has been
found up to the present only in two districts, namely, the Jeypore
agency in the Madras Presidency, and Nagpur in the Central Pro-
vinces ; and A. elegans in only one place in the Bombay Presidency.
It even happens, not infrequently, that the anopheles fauna of two
places only a few miles apart is entirely different. In some cases this
localized distribution of species is due to differences in the charac-
ter of breeding grounds. In Calcutta, for example, almost the only
breeding places are ponds and pools of water the favourite breed-
ing grounds of A. rossi, while in the Duars the prevailing breeding
grounds are running streams — the favourite breeding places of Af
listoni. Climate is also an important factor, as in the cases of A.
lindesayi and A. gigas, which are found only in hill districts, and a
particular kind of food supply may also have some influence, as in the
case of A. rossi, which is never found very far from human dwellings.
42]

Climate and Season.

As regards the abundance of " anopheles" present in any district,
it is well known that they may be very numerous in one place and
scanty or almost unknown in another, and also that, while one specie8
is very abundant, another may be very rare. Other things being
equal, this dissimilarity in prevalence is due to differences in the num~

ber, extent,
and character,
of breeding
grounds, and,
as a general
rule, it may
be said that
there is a
direct relation
between the
extent and
proximity of
breeding
grounds and

o

the number of
" a n o pheles "
present in any
place. The
prevalence of
these insects
varies also ac-
cording to the
season of the
year, and the
influence of
this factor is
more marked
in the case of
some species
than of others.
The accom-
panying chart
illustrates
the seasonal

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Curve of irrigation suppLy Co
Mi<3.n Mir fciverdg'e of 7 years).

Curves of A .CuHcifaciea.
R<3.inf<al,t, f average i868-JQ92h
Curve of A.Rossii,.

Fig. 9.

[43

Hibernation.

prevalence of A. culicifacies and A. rossi in the Punjab. It will be
seen that A. culicifacies begins to be prevalent in May, while A. rossi
does not appear until July, and that both species diminish rapidly in
numbers towards the end of November. A. fuligmosus is most
prevalent in the Punjab in September, but as the winter advances
it does not decrease in numbers nearly to the same extent as other
species do, and throughout the winter its adults may be found with-
out difficulty in houses, and its eggs and larvae in newly-formed
breeding places. A. pulcherrimus is also, to some extent, a " winter
species " in the Punjab, and non-hibernating specimens can be col-
lected in moderate numbers even during the coldest months. Re-
garding the seasonal prevalence of other species which occur in the
Punjab, and of all species which occur in other parts of India,
little or nothing is known.

THE METHODS BY WHICH ANOPHELES TIDE OVER THE WINTER.

Two methods of which mosquitoes tide over the cold season are
usually described, viz. (1) by the hibernation of adults, and ( 2) by the
hibernation of larvae. Very few observations on this important
subject have, however, been made in any part of the world, and it
is by no means certain that these are the sole methods by which
the disappearance of " anopheles" during the winter, and their
reappearance in the spring, may be accounted for. The only
observations recorded in India appear to be those made by one of
us in connection with the anti-malarial operations carried out at
Mian Mir in the Punjab during 1901-1^03. These were as follow :

(1) During the winter not a single adult A. rossi or A. culicifacies
could be found by the most careful search, or by burning culicidal
substances, in any house, stable, shed, or other place where it seemed
probable mosquitoes might hibernate during the cold weather ;

(2) no eggs or larvae of either of these species appeared in newly-
made breeding places ; (3) in permanent breeding places, which
had remained since the summer, many hibernating larvae of
.4. culicifacies were found, but no larvae of a. rossi were present ;
(4) many adult A. fuligmosus and a few adult A. pulcherrimus
were found throughout the winter in houses and sheds. The
habits of these species were, however, the same during the winter
as during the summer, and they did not " hibernate " in the correct
sense of the term ; ( 5 ) eggs, young larvae and pupae of these two

44]

Distance 'of fliq ht.

species were found throughout the winter in newly-made breeding
places.

It will be seen, therefore, that none of these four species hi-
bernated in the adult form, but A. culici fades was undoubtedly
able to tide over the winter by hibernating in the larval form. A.
fuliginosus and A. pulcherrimus appeared to be able to pass the
winter without any change taking place in their habits. Both
adults and larvae of .4. roW so far as it was possible to ascertain
by careful search and experiment, seemed to have disappeared
entirely during the winter. There are other facts which lend weight
to the supposition that A. rossi disappears from the Punjab during
the winter, one of which is the recently discovered fact that this
species can fly a long distance, and another the fact that it cannot be
found in the Punjab until the beginning of July. If adults of this
species were present in houses in a hibernating condition during the
winter, it is practically certain that they would become aroused from
their state of torpor and that the species would become sufficiently
prevalent to be easily found in April, when the hot weather begins.
It is perhaps not too much to conclude from these facts that at
the onset of the winter, A. rossi " migrates"-— perhaps by short
stages — to places further south, and when the summer comes,
reappears in the same way.

DISTANCE OF PLIGHT.

With regard to this question, also, very few trustworthy obser-
vations have been recorded. It is usual to say that the normal
distance of flight of " anopheles " does not exceed half a mile. Evi-
dence in support of this statement was obtained by the members
of the Royal Society's Malaria Commission in India. These
observers found that in certain villages in the Central Provinces
A. culicifacies, A. stephensi, and A. fuliginosus were always
present in abundance if there were extensive breeding places
within a quarter of a mile, but that villages, which were distant
half a mile from such breeding places, contained few or no " ano-
pheles." From this they concluded that the latter distance was
beyond the normal flight of these species. In Mian Mir three
groups of rain-formed pools afforded an opportunity of making
further observations on this point. The first group was 450
yards distant from any house, the second 750 yards distance,

[45

Anopheles fly a long distance in search of food.

and the third upwards of three quarters of a mile. On repeated
occasions the pools of the first group were found to contain larvae
within a week of a shower of rain, on three out of four occasions
the pools of the second group contained larvae, but on no occasion
were larvae found in the pools of the third group. These experi-
ments appeared to show that A. rossi, which was the species
concerned, would readily fly to a breeding place a quarter of a
mile away, that it would less readily fly to breeding places 750
yards away, and that it would never fly to breeding places three-
quarters of a mile away. It is obvious, however, that from none
of these experiments can any knowledge of the maximum flight of
"anopheles" be obtained ; they prove only that when these insects
are once established in a village they naturally select the nearer
breeding places in preference to those which are further away.
But in their search for food adult "anopheles " often become attracted
to villages which have no breeding places near at hand, and recent
observations have shown that they may be abundant in a place
even when there are no breeding grounds within a very long
distance. Captain James, I.M.S., in the operations at Mian Mir
already referred to, found on one occasion that numerous adult
4. ful'iginosus were present in the bazaars and houses when no
larvae of this species were to be found nearer than two and a quarter
miles, and Dr. Christophers, during the same operations, found
that the limit of flight of A. rossi had not been reached at three
quarters of a mile, and that although all breeding places of this
species had been obliterated up to this distance, it still appeared in
increasing numbers in the houses. The latter observer draws the
following conclusions from his experiments :-—

(1) In every case where an abundant food supply existed,

anopheles travelled long distances (half a mile or
more) to reach it, and traversed an equal distance, if
necessary, to lay their eggs. Where, however, a suit-
able breeding place lay near at hand they did not
appear to pass it over.

(2) The maximum distance of flight of A. rossi is not known

with certainty, but under the conditions at Mian Mir
the experiments showed that they flew to and fro a
distance of more than half a mile.

Mode of spread of " Anopheles"

(3) The breeding places of A. fuliginosus were in no case

nearer than 1,000 yards from the situation where the
adults were captured.

(4) In the later part of the season it was difficult to understand

where adult A. culicifacies came from unless distances
of half a mile or more were traversed by this species.
It is obvious that in any attempt to estimate the probable

efficacy and practicability of efforts at destruction of " anopheles,"

these conclusions are extremely important.

MODE OF DISPERSAL.

The usually accepted fact that " anopheles " do not disperse any
considerable distance from the place where they were born may also
be contested. In our opinion, which is based chiefly upon observa-
tions made by one of us, and by Dr. Christophers, in Mian Mir, four
ways of dispersal of " anopheles " are constantly in action in India,
viz. :

(1) By direct flight over considerable distances. Examples

of this method have already been given.

(2) By eggs and larvae being carried long distances by

streams and canals.

(3) By the gradual spreading of "anopheles" adults in all

directions, by short stages, from areas in which they
are abundant. This results from the fact that all
newly hatched mosquitoes do not return to the house
or village from which their parent came, but fly to
houses in the opposite direction ; and having found
their food there, proceed to breeding places still
further removed from the original village.

(4) Adult mosquitoes are constantly conveyed — sometimes

long distances— in carriages, carts, and other vehicles.
This must be a matter of common observation to any
one who has occasion to travel much in India.

Observers who consider that " anopheles " can be materially
reduced in numbers by the obliteration of all breeding places in the
immediate vicinity of dwellings, rely chiefly upon the suppositions
that the range of flight of these insects is very limited, and that
they do not disperse any considerable distance from their breeding

[47

Breeding grounds of " Anopheles"

grounds. It would appear probable, from the observations just re-
corded, that such suppositions are incorrect, and if this is so, the
task of materially reducing the numbers of " anopheles " in any place
will undoubtedly be one of great magnitude.

THE BREEDING PLACES OF ANOPHELES.

The fact that, taking " anopheles " as a whole, it is almost impos-
sible to mention any collection of water in which their larvae may
not occasionally be found, is now well known. It has an important
application when any practical measures at extermination of larvae
are attempted, in that it leads us not to overlook even the most
unlikely places in our search for larvae ; for unless we search systema-
tically every collection of water, temporary or permanent, we may
easily allow an important breeding place to remain, when we think
all possible breeding grounds have been done away with.

But under favourable conditions — by which we mean abundance
of breeding places of all kinds near at hand — " anopheles " will not,
as a rule, lay their eggs in an unsuitable collection of water, and
there is no doubt that, under such circumstances, not only do these
mosquitoes select their breeding places, but that each species has a
particular kind of breeding ground that it prefers over any other.
This observation which was first made by Dr. Christophers at Jal-
pniguri in Bengal, is a very important one.

At Jalpaiguri two species of anopheles were common, viz. — ^.
rossi Giles, and .4. nigerrimus. The breeding places of A. rossi
were invariably found to be the small, shallow, muddy puddles and
pools close to, and among, the native huts. A. nigerrimus, on the con-
trary, was breeding entirely at some ditance from the village in the
deep natural pools of a swampy marsh. A. rossi larvae were never
found in these pools, and A. nigerrimus larvae never in the shallow
muddy pools near the huts.

In the Duars, the same selection of breeding places by A . rossi
and A. listoni, was found to exist, A. rossi larvae being found only
in the shallow muddy pools near the coolie huts, and A. listoni
larva? ( the adults of which were nevertheless more common in the
huts than those of A. rossi) being only found at some distance
from the lines in the small clear pools formed by a mountain stream,
and by dipping in the water among the grass and weed at the edge
of the stream itself.

Selection of breeding places by different species.

The principle indeed extends to all the species of Indian
" anopheles," and an excellent example of its application to the
three species A. culicifacies (Giles), A. fuliginosus (Giles) and
A. rossi was found in an isolated bazaar at Mian Mir. This
bazaar is surrounded by an irrigation channel about four feet wide
and three feet deep. At the upper end of this water-course and
about ten yards from it are a number of broad shallow muddy
pools. At the lower end of the water-course and about thirty
yards from the bazaar is a swampy piece of land covered with thick
trees and shrubs, and containing a number of deep clear pools in
which water plants and weed have grown. The adults of the three
species A. rossi, A. culicifacies, and A. fuliginosus were present
in the houses of the bazaar, and we should have expected that the
larvae of all the species would have been found together in some
or all of the breeding places. This, however, was not the case. In
the irrigation channel no other larvae than those of A. culicifacies
\vere ever found, in the shallow muddy pools no other larvae than
those of A. rossi, and in the clear deep pools under the trees no
other larvse than those of A. fuliginosus. It is evident therefore
that each of these species had selected a particular kind of breeding
place. The plan of the Royal Artillery lines in Mian Mir, given
on the following page, illustrates the chief breeding places of
" anopheles " in this portion of the cantonment. The Iarva3 of A.
culicifacies were confined almost exclusively to the irrigation canals,
while those of A. rossi were present only in the numerous rain
formed pools which covered the plain on every side.

In another part of Mian Mir an example of selection of breeding
places by another species of " anopheles " was found. In this
place several species were present in the barracks of the native
troops, and there were abundance of breeding places of different kinds
near. The larvse of only one species, however, viz., A. stephensi
were found in the earthenware vessels of water kept in the lines,
and the larvae of this species were never found in any of the
other breeding places, — a good example of selection of a breeding
place by this species.

The breeding grounds of the species of " anopheles" at Mian Mir
agreed with what had been found for the same species in other
parts of India, and it is possible to divide the Indian " anopheles,"

[49

Favourite breeding grounds.

as regards their breeding grounds, into at least three groups, via.
(I) those which breed almost exclusively in running water, (2) those
which breed in shallow muddy pools in the vicinity of dwellings

STC£ UN£S~

if.

w

t *

CANT

Plan of RoyalArtillery Lines in Mian Mir.

and in tins and gumlahs of water ; and ( 3 ) those which breed at
some distance from houses in deep natural pools with much aquatic
vegetation and in marshes.

The favourite breeding grounds of some of the species of Indian
" anopheles " may now be summed up :—

A. listoni. — The larvae of this species are found most frequently
in quickly running streamlets with grassy edges. Their presence
in a stream can be detected only by dipping with a tin among the
grass and vegetation at the edge of the stream and in the pools and
backwaters.

A. culicifacies. — This species is essentially a breeder in slowly
moving water. It will be found in canals, ditches and streams when
quite absent from neighbouring shallow stagnant pools. Irrigation

so]

Breeding grounds of different species.

canals are its favourite breeding place in the Punjab. In places
where there is no running water it may be found in clear pools, as
at Ennur, near Madras, where it was breeding in the borrow-pits by
the side of the railway. It has also been found in rocky pools in
the bed of a river.

A. nigerrimus. — The larvae of this species are found chiefly in
deep dark natural waters with much aquatic vegetation Favourite
breeding places are deep overgrown canals, swamps in the jungle,
and ponds with water weeds. Its breeding places aye not, as a rule,
found near houses. The larvae are generally scattered singly among
the water plants at the edges of the pool and can be caught only
by dipping with a tin or muslin net among the plants and weed.

A. barbirostris. — The breeding places of this species are practi-
cally the same as those of A. nigerrimus. In Lahore the larvae
were present in the lily ponds in the public gardens until the end
of November.

A. fuliqinosus (Giles). — The larvae of this species are often
found along with those of A. nigerrimus. As a rule, however, it
prefers more open water and more sunlight In Madras and in the
Central Provinces it was common in the large open tanks with
grassy edges.

A. jamesi (Theobald). — In the Central Provinces the larvae of
the species were found among the grass and water weeds at the edge
of a large open lake In Travancore (Quilon) in a large sandy tank.

A. rossi. — The breeding places of this species have already
been sufficiently referred to. Its larvae are never found at any
distance from houses. Shallow muddy pools are its favourite breeding
ground, and hundreds of larvae are usually present in the same small
pool, so that the larvae of this species are the ones which are
most frequently found by observers, as they are easily detected by
inspection. The larvae of most other species have to be fished for
with a tin or net. In Madras, rossi larvae are common in the irri-
gated rice-fields and in the muddy tanks, as well as in pools made by
digging for building purposes, in brick-fields and in cultivated areas.

A. stephensi. — In Mian Mir (Punjab) this species was found
to be breeding only in the earthenware gumlahs and tins kept
full of water in the lines of the native troops. In Madras it was
found to be breeding only in the disused wells in the native

[51

The test-pool experiment.

and Eurasian houses. It is probable that since the introduction of
a pipe water-supply into Madras city, the numbers of this species
have largely increased, for its larvae are only found in those wells
which, since the introduction of the pipe water-supply, have been
unused.

A, maculatus. — The larvae of this species may be found further
from houses than those of A. rossi, and whereas larvae of the latter
species are usually found in muddy water, the larvae of A. maculatus
prefer clear sandy or rocky pools. In the Duars its larvae were
found in clear pools on a rice-field. In Hong-Kong (China) its
larvae were found by one of us in the small marshy pools on the
granite soil of Kowloon.

Sumc.ent observations have not been made with regard to the
remaining species of " anopheles " to enable their favourite breeding
places to be particularised, but details of the breeding places in which
their larvse have been found will be given in Part II.

Under unfavourable conditions the selection of suitable breeding
places by the different species is not of course so apparent, and
many instances might be given tending to show that if all the suit-
able breeding places near a village are dried up, " anopheles " will lay
their eggs on any collection of water of any kind. The " test-pool "
experiment of Stephens and Christophers in Africa is sufficient to
prove this, and the same expedient for finding out whether adult
" anopheles " are really present in a place or not, when all the natural
breeding places have disappeared, has been frequently resorted to
by observers in India.

Even without making artificial pools in a village many examples
of the fact that in the absence of more suitable breeding places,
" anopheles " will lay their eggs in almost any collection of water, may,
be found in nature. In one part of Calcutta (Hastings) in Junes
when no breeding place could be found anywhere near, and no adults
could be caught in the houses, larvae were found in the cisterns of
water on the roofs of the houses. During the hot weather in
Mian Mir (Punjab) also, when the irrigation canals had been
stopped for some time, and there were no natural breeding place
of any kind, " anopheles " larvae were found in very curious
situations, as for instance in the swimming bath, in the horse
troughs, in tins of water accidentally left about, in the small drains

52]

Domestic and wild species.

which carry off the water from the stand-pipes, and in the small
stone reservoirs in the gardens.

These facts point to the necessity of constant and careful
search in every collection of water when any efforts at extermination
of larvae are attempted, and although we may certainly say that
under favourable conditions we are more likely to find " anopheles "
larvae in certain collections of water than in others, and that under
such conditions the different species will select different kinds of
breeding places, no hard-and-fast rule, which might perhaps prevent
us from searching a particular place, can be made.

DOMESTIC AND WILD SPECIES. THE DIFFICULTY OF ESTIMATING THE RELA-
TIVE ABUNDANCE OF DIFFERENT SPECIES.

It is a well recognised fact that some species of " anopheles "
are more commonly found near villages and dwellings than others.
We may, in fact, divide these insects broadly into two classes : the
" domestic " species, which are usually found near human dwellings,
and the " wild " species, which are rarely found in houses. Of the
first class, A. rossi is a typical example, and of the second A. bar-
birostris. Some species would appear, as regards this habit, to
occupy a place intermediate between the typically domestic and
the typically wild species. A. fuliginosus, for example, may, in
certain parts of India, be found in enormous numbers in the sheds
and outhouses on the outskirts of a village, while in other parts,
though large numbers may be caught in tents pitched at some
distance from a village, few or none will be found in the houses of
the village itself.

It is usual to say that the greater the number of " anopheles "
there are in a place, the greater will be the prevalence of malaria.
This is not by any means borne out by experience. We have
already mentioned that some species of " anopheles " are better
malaria-carriers than others, and apart altogether from the fact
that " anopheles " may be abundant in a place without there being
any malaria there at all, it often happens that the species which
is present most abundantly is not the one which is carrying malaria
at the time. It is, however, a difficult matter to estimate the
relative abundance of different species in any place, for some are
much more easily seen than others, and the habits which some

[53

The relative numbers of different species.

species have of secreting themselves among the straw of a thatched
roof and of resting only upon objects which are as nearly as
possible the same colour as they are themselves, are very important.
In order to exemplify this, it seems worth while to recount an
instance which happened in our experience. In the malarious
village of Ennur in the Madras Presidency, A. rossi was so
abundant that on almost every straw of the thatched roof of every
house three or four specimens of this species were resting. A
careful search in the ordinary way did not reveal the presence of
any other species, and it is certain that, had there been no other
object in the search than the mere determination of the species of
" anopheles " present in the village, the observer would have gone
away quite satisfied that A. rossi was alone present. But the
village was an extremely malarious one, and knowing that
A. rossi was an inefficient carrier of malaria in nature, he was un-
willing to believe that no other species was present in the houses.
Fixing his mind, therefore, upon the thought that he was looking
for A. culicifacies and not for A. rossi, he again commenced the
search with great care, and was rewarded not only by detecting the
presence of A. culicifacies, but by catching a sufficient number of
this species during several days' work, to prove that it was the
species responsible for the prevalence of malaria in the place and
not the very much more abundant species A. rossi.

THE FOOD OF ANOPHELES. THEIR NOCTURNAL HABITS.

Mr. Theobald reports that one species of "anopheles," viz., A.
maculipennis, does not habitually feed on blood in England. Nuttall
and Shipley, however, found that this species readily sucked blood in
laboratory experiments. All the species known to us in India certain-
ly feed chiefly, if not entirely, on the blood of men or of animals.
In laboratory experiments seven species, with which experiments
were made, readily sucked blood every night for several weeks, in
spite of the fact that they had not completely digested their previous
meals. Fuliginosus, culicifacies, listoni, and rossi also fed readily
on the blood of pigeons and sparrows.

Anopheles feed almost exclusively at night or in the early
morning just before dawn. During the daytime, even if they are
taken into a dark room, it is almost impossible to get them to
suck blood. Exceptional instances have been recorded — and have

54]

Noctttrnal habits.

occurred in our own experience — in which " anopheles " flew about
and even attempted to feed in broad daylight, but, as a rule, they are
strictly nocturnal in their habits. This fact was long ago brought
forward by one of us in support of the view that in many parts
of India these mosquitoes act as the usual intermediate hosts of
Filaria nocturna, the embryos of which, as is well known, are
present in the peripheral blood only at night. The readiness with
which " anopheles " can be killed by placing the bottle containing
them for a short time in bright sunlight, the fact that they are
found during the daytime only in the darkest corners of rooms,
that they seldom or never rest upon light-coloured clothes or on
cleanly whitewashed walls, and the fact that whereas " culex" mos-
quitoes emerge from the pupa case at any time of the day or night,
"anopheles " very rarely emerge until evening, all point to the
conclusion that these insects are essentially nocturnal in habits.

THEIR LENGTH OF LIFE.

The usual length of life of adult " anopheles " is not known with
any exactness, but it is certainly considerable. Although the habit
of hibernation has not been observed in any of the Indian species,
Annett and Button have described it in the English species A,
maculipennis, which must therefore be capable of living at least
some months. It is also well known that adult " anopheles " can sur-
vive throughout the whole of the hot weather in India and Africa,
even when all breeding places are dried up. According to Stephens
and Christophers the adults remain during this time in the houses,
and though they feed regularly, they do not lay eggs, even when
artificial breeding places are made. One of us has also recorded
the fact that " anopheles " caught in houses at Ellichpur, in the
Berars, between March and June did not lay eggs, though they
readily did so at other times of the year. Stephens and Christo-
phers describe the habit of remaining in houses during the hot
weather under the term " a3stivation." Adult "anopheles" may,
with care, be kept alive in captivity for two months or more.

THE " SWARMING " OF ANOPHELES.

In his account of the anti-malarial operations at Mian Mir,
Dr. Christophers describes, under the heading of " The Swarming
of Anopheles," a habit which had not previously been noted with

[55

Swarming.

regard to these insects. A rossi exhibited the phenomenon in the
greatest degree. In July, larvsa of this species were practically
never seen, and even for some time after the onset of the rains its
larva? were never found in the numerous pools then formed. By
the third week after the commencement of the rains its larvaa were
present in many pools, and by the sixth week they were very
abundant. By the middle of September larvae of this species were
present in enormous numbers in all the pools round the bazaars and
in most of the pools throughout the whole country-side. The adult
insects showed a corresponding increase, and though found with the
greatest difficulty before the onset of the rains they were present
in immense numbers in every bazaar and village in the neighbour-
hood a few weeks later. In spite of the fact that a reduction in
breeding places occurred at the end of September, they remained in
large numbers until the end of October and then rapidly disappeared.

THE CHARACTERISTIC POSITION ASSUMED BY ANOPHELES WHEN RESTING

ON ANY SURFACE.

Many mosquitoes can be immediately recognised as " anopheles"
by the characteristic position which they assume when resting on a
wall or roof. From a short distance they look somewhat like
thorns projecting from the surface (PL III, 5, 6). The reason why
"anopheles" rest in such a characteristic position would seem to be
that the proboscis, head, thorax and abdomen of a mosquito of this
kind lie in one straight line, so that when the proboscis is directed
towards any surface, the abdomen is directed away from that surface.
The angle formed between an anopheles and the wall on which it
is resting differs with different species, and with practice it is often
possible to name a species by merely observing the angle which
it forms with the wall. A. rossi, for example, rests at an angle
of about 45° with the wall, while A fuliginosus forms very nearly a
right angle with it. Culicifacies, aitkeni and culiciformis lie almost,
if not quite, parallel to the surface on which they are resting,
and Annett and Dutton have shown that in a state of hibernation
macutipennis does not form an angle with the surface upon which
it is resting, but lies with its whole body nearly touching the
wall. It will be noticed, however, that the proboscis, head, and
body of an " anopheles," in whatever position it is resting, are always

56]

The characteristic position of anopheles.

in the same straight line. On the other hand, the abdomen and
thorax of a " culex " always form an angle with the head and proboscis,
so that these mosquitoes appear " hunch-backed."

SOME CHARACTERISTICS OF THE LARV^ AND EGGS NOT DESCRIBED IN

THE PRECEDING PAGES.

1. The food of anopheles larvce. — This consists chiefly of
minute water animals, which abound among algae and other water
plants. Larvae cannot subsist upon a vegetable diet alone, and the
duration of the larval stage depends chiefly upon the supply of
animal food. When this is small in proportion to the number of
larvae, the stronger larvse kill and eat the weaker.

2. The duration of the egg stage and the resistance of ova to
drying. — When anopheles eggs are laid on water, they almost in-
variably hatch out into larvae in 48 hours. When they are laid, as
they frequently are, upon damp mud, the development of the
embryo goes on inside the egg, and when water is added to the mud
the larvae hatch out immediately. This observation, which was first
made by Captain Liston at Ellichpur in the Berars, has lately been
confirmed by Dr. Christophers at Mian Mir. The latter observer
found that, after the water in an irrigation canal or pool had been
emptied out, " anopheles " still laid their eggs on the soft mud, and if
water was again allowed to enter the canal or pool before the mud
had become completely dry, numerous young larvae would almost
immediately be found in it. It is not difficult to detect eggs which
are laid on the edges of pools in this way. Dr. Christophers col-
lected a number from pools of different degrees of dryness and
placed them on water with the following results.

Number of ova Number of larvae Additional number

Character of mud. , , , , , , . n K

taken. hatched in 15 minutes, eventually hatched.

Quite soft ... 12 0 12

Cracked but moist ... 10 2 8

Quite dry ... 25 5 1
Slab of soft mud with

ova ; dried 12 hours. A large number 0 0
in the sun

It will be seen, therefore, that pools which are, to all intents and
purposes, quite dry, may contain numerous larvae almost immediately
after a shower of rain.

[57

Other characteristics of larva and eggs.

3. The resistance of larvce to drying. — Dr. Christophers also
found that larvae could remain alive on soft mud even after exposure
to the sun for several hours. If the mud had so far dried as to
lose its glistening surface the larvae were found to be dead.

4. The duration of the larval stage. — Dr. Liston found that,
under suitable conditions, " anopheles " larvae became pupae in about a
week, but that with an unsuitable or deficient food-supply they re-
mained as larvae for more than a month. At Mian Mir in Septem-
ber (the most favourable month), Dr. Christophers found that A.
rossi did not pupate until the twelfth day after the eggs were laid.
No difference was noted in the case of shallow or deep pools,
although the temperature of the water in the shallow pools was
high, viz., 96° F. to 102° F., while that of the deep pools was only
90° F. or less. The adult insects emerged two days after pupation, so
that fourteen days ( two in the egg form, ten in the larval form and
two in the pupal form ) would appear to be about the minimum time
required for the development of rossi from the egg to the adult stage.
The least time in which culicifacies developed from the egg to the
adult stage was thirteen days. The same observer remarked that
" anopheles " were slower to develop than any other kind of mosquito,
taking three days longer than Oulex and four days longer than
Stegomyice.

In the winter months the development of larvae may be almost
indefinitely delayed, and, as already mentioned, the larvae of some
species may remain without developing into pupae throughout the
whole winter (hibernation of larvae). Whether this is due to the
temperature of the water being lower, or to a difference in food-
supply, is not known, but the experiments of Dr. Christophers
recorded above would seem to show that the temperature of the
water has little or no effect. There is also a great difference
between different species in this respect, for in the Punjab while
the larvae of culicifacies remain in a hibernating condition
throughout the winter, those of fuliginosus develop into pupae
and adults even in the coldest months.

58]

CHAPTER IV.

THE CLASSIFICATION OP ANOPHELES.

;E shall attempt to consider this subject from the
points of view of the amateur naturalist and of
the worker on tropical diseases. When reviewing
a large number of animals or plants naturalists
divide them into groups which resemble one
another in different degrees. The largest group
or class includes many groups of orders. Each order includes subor-
dinate groups called families, and each family subordinate groups
called genera, under which again are grouped a number of species.
Finally each species includes a number of varieties. The foundation
of all these groups is laid in the groups of species, and in order to be
able to appreciate the value of any classification, it is necessary to
know exactly what is meant by this term. The word literally means
a look, an appearance, a kind ; beings which look the same are said to
be of the same species. In its natural history sense a species means
a group of individuals which closely resemble one another. A
species is subordinate to a genus — a wider group of similar, but
less closely similar forms — and is superior to a variety, of which
there may be several in a species. We may attempt to define the
limitations of the term " species " by the aid of examples. If, for
instance, we were to examine a number of children of the same
pair of parents we should note differences in their stature,
features, complexion, and in the colour of their hair and eyes, but
it is obvious that such differences — which Darwin has termed
" individual differences" — cannot be ranked as specific. The first
limitation of the term " species " must therefore be that individuals,
which are classed as belonging to different species, must present
greater differences than are exhibited between the offspring of any
single pair of parents.

The second limitation would appear to be that the differential
characters of species must be constant from generation to generation.

[59

Definition of species.

That this must be so is shown by the occasional appearance
of " monstrosities," which differ markedly from their progenitors,
but which cannot be classed as belonging to a different species
because they are incapable of handing down to succeeding genera-
tions such abnormal differences. By many authorities a third
defining limit has been applied to the term " species." They believe
that true species, when intercrossed, are often sterile, and, when
fertile, the hybrids produced are almost always sterile. Varieties,
on the other hand, are almost always fertile.

The idea of species, then, must rest on three orders of facts :
(l) the morphological resemblances between individuals; (2) the
lineal transmission of distinctive characters ; and (3) the sterility of
first crosses between species or their hybrids.

Although the practical application of this definition of species
is involved in many difficulties, we may reasonably expect that some
attempt to conform to it should be made by naturalists. It is well
known that entomologists are particularly neglectful in this respect,
and that they have recorded a vast number of forms as distinct
species on the strength of single specimens and without any know-
ledge of their generation. In the large majority of cases the species
of mosquitoes have been established solely on the morphological
characters of dead specimens. We think it is not unreasonable to
expect that before an entomologist decides to class any mosquito as
the representative of a new species, or a new genus, he should
consider whether it represents merely an " individual difference,"
a " monstrosity " or a " variety." To workers in India it is well
known, for example, that the different individuals hatched out from
the same batch of mosquito eggs vary greatly in size, and we have
found that the adults developed from any batch of eggs of A.
culici/acies can almost always be readily divided into a group of
large and a group of small individuals. Yet size is a character not
infrequently relied upon by Mr. Theobald for the separation into
distinct species of two mosquitoes alike in other respects. His species
Myzomyia minutus. for example, which was described from a single
specimen forwarded to him from Lahore, would appear to have been
founded upon this character alone, and the same character is used as one
of the points of distinction between A. funestus and A. rhodesiensis.
Under the heading of " individual differences " comes also the question

60]

Individual differences : dimorphism : abnormal forms.

of dimorphism, one instance of which among " anopheles " mosquitoes
is well known to us. Major Adie, I.M.S., found that in the Punjab
two distinct forms of A. fuliginosus are prevalent during October and
November, viz. : the usual form with three white bands on the palpi
and three white hind tarsal segments, and a second form with four
white palp bands, only two white hind tarsal segments, and slightly
different wing markings. It is quite certain that, had specimens
of these two mosquitoes been sent to England for identification,
they would have been described as distinct species, for Mr. Theobald
has founded many of his species upon less marked differences than
exist between these two forms. Breeding experiments showed,
however, that both forms could be produced from a single pair
of parents presenting the characteristic markings of the more
usual form, viz., that with three white palp bands and the three
terminal hind tarsal segments white. Observations carried on
throughout the winter showed that in December and January the
usual form was replaced almost entirely by the second form, and
that with the onset of spring a return to the ordinary form
occurred — an excellent instance of seasonal dimorphism.

Secondly, there is the question of abnormal forms or mon-
strosities. During his examination of the types of A. rossi deposited
in the British Museum, Mr. Theobald encountered a specimen the
abdomen of which was covered with scales arranged as in mosquitoes
of the genus Culex. Many thousand specimens of " anopheles " of all
kinds had been examined, and this was the only instance in which the
abdominal scale structure had resembled that of " culex " mosquitoes.
To us it appears very probable that this is an instance of a mon-
strosity, and from the remarks in the introduction to his " Revision
of the Anophelina " it is evident that Colonel Giles shares the
same view. Mr. Theobald, however, classifies the insect without
question as the type of a new genus (Aldrichia). Another
instance of a monstrosity, which is perhaps even more marked
than the above, is the specimen on which Mr. Theobald has
founded a new sub-family called Heptaphlebomyina. The single
insect, on the characters of which this new sub-family rests, was
provided with seven longitudinal veins on its wings instead of
only six, as had been the case with every mosquito examined up
to that time.

[6.

Variation.

Lastly, there is the difficult question of variation. To any one
who has read Mr. Theobald's monograph carefully it will be
apparent that he takes little or no account of the numerous varia-
tions which occur among the different species of mosquitoes, and
that he considers the slightest differences, often microscopic,
as of specific value. In the limited space at our disposal it is
impossible to describe even the structural variations which are met
with in members of the same species of mosquito, but by taking an
example we may note the slender grounds upon which many of
Mr. Theobald's species are based. For this purpose we may
consider the four mosquitoes, funestus, listoni, culicifacies
and rhodesiensis. In the first volume of Mr. Theobald's
monograph these four species are distinguished from one another
chiefly on account of differences in the relative positions of the
cross veins of the wings — a character upon which, as being struc-
tural, the author laid much stress. We were able, however, to
show that even in a series of individuals of any species from
the same batch of eggs the relative positions of the cross veins
varied greatly, and in the third volume of his monograph Mr.
Theobald admits that the character is of no value as a means of
differentiating closely allied species, and relies entirely upon colour
differences. As regards funestus he says : "It comes very
near listoni, but can be at once told by the palpal banding
being different, the three white bands being unevenly disposed,
the two apical ones being nearer together than in listoni The latter
species has also a very prominent white-scaled third longitudinal
vein ; in funestus it may be entirely dark or may have a white
patch, but is never so markedly pale as in the Indian species." Thus
the two points upon which Mr. Theobald relies for specific distinc-
tion are differences in the palp banding and differences in the mark-
ings of the third longitudinal vein. Unfortunately, however, he
is not consistent, for in the preface to this volume he says : "These
(palp) bands are only colour effects, and specific distinctions cannot
be based on such ; moreover, specimens may frequently be met with
showing variations in this respect." He also recognises that great
variations occur in the markings of the third longitudinal and other
veins of the wings, and describes two varieties of funestus, in one
of which the third longitudinal vein is dark, as in rhodesiensis

62]

Mr. Theobald's classification.

(and culicifacies), and in the other it is pale scaled in the middle
(as in listoni). Without entering into details it will suffice to say
that we have found varieties of listoni and culicifacies, which present
exactly the same markings as Mr. Theobald would have us believe
are constant characteristics offunestus and rhodesiensis, and it will
therefore be apparent that such characters are insufficient for the
separation of these species.

While we are thus enable to recognise any constant difference
between listoni and funestus, except that the former is found in
India and the latter in Africa — a fact which loses its significance
when it is known that several other species of "anopheles" occur in
both countries — we are also unable to state definitely that culi-
cifacies, for example, is a species distinct from listoni. We
should be inclined to class these " anopheles " in Wallace's local
forms, or geographical races or sub-species ; they are moderately
constant and distinct in each locality, but when all the forms from
several localities are compared, the differences are seen to be so
slight and graduated that it is impossible to define or describe
them, though at the same time the extreme forms are sufficiently
distinct.

In view of the difficulties which we have attempted to outline
above, we have decided not to adopt any dogmatic opinion as to
the distinctness of many of the species of " anopheles," until further
study of these insects in their natural state has been made.

For the same reasons we are unable to accept Mr. Theobald's
new classification of "anopheles" into different genera, for not only do
the differences between many of the new genera appear to us to be
so slight as to be of no more than specific importance, but it has
yet to be shown that the shape and arrangement of the scales are
constant in the individuals of any given species of mosquito.
Darwin has laid it down that " a classification founded on any single
character, however important that may be, has always failed ; for
no part of the organism is invariably constant," and we think that
if a sufficient number of individuals of any species of " anopheles "
were examined, considerable variations in the shape and arrangement
of the scales would be found.

The question may also be looked at from the point of view of
the worker on tropical diseases. In recent years entomologists

[63

Some objections to it.

have taken up the study of mosquitoes solely on account of their
importance in tropical medicine, and, in the words of Professor Ray
Lankester, "so as to enable the medical men engaged in tracing
the connection between mosquitoes and human disease to identify
and speak with precision of the species implicated." The ease
or difficulty with which mosquitoes can be identified depends, to a
great extent, upon the method by which they are classified, and it
would therefore have been advantageous to medical men in the
tropics if Mr. Theobald had chosen some more marked and more
easily recognisable character than scale structure for the foundation
of his classification. The three questions which a worker on tropi-
cal diseases might reasonably ask when he comes across a new
method of classifying mosquitoes are : —

(1) Is the new classification necessary ?

(2) Will it render the identification of species an easier

matter than before ?

(3) Does it bring those species which are alike in habits

and pathological significance into the same groups ?

We believe that, as regards Mr. Theobald's new classification
of " anopheles," all these questions must be answered without hesita-
tion in the negative.

That the further sub-division of the genus Anopheles (Meigen)
is unnecessary, is shown by the fact that in any particular country
the number of valid species of " anopheles " is so small that there is
no real difficulty in distinguishing between the different species.
Even after having worked for only a week or two at the subject an
observer easily learns to ascertain the specific name of any specimen
of " anopheles " which he encounters.

As regards the second question, we believe we are expressing
the opinion generally felt by medical men in the tropics when we
say that the new classification adds much confusion to an already
difficult subject, and renders the correct identification of specimens
a much more difficult matter than before. We have not yet met
any one who could, in all cases, correctly ascertain the generic names
of specimens of " anopheles," according to Mr. Theobald's classifica-
tion, and the fact that numerous changes have been made in the
position of species since the new classification was first instituted

64]

Difficulty of assigning specimens to their correct genera.

indicates that Mr. Theobald is himself somewhat uncertain about
the matter. Colonel Giles gives an instance of a species which
formerly figured as the type-species of a genus, but which has now
been relegated to a humble position in quite another genus, and we
have ourselves sent home specimens of A. stephensi which, on one
occasion, were identified by Mr. Theobald as belonging to the genus
Nyssorhynchus and on another to the genus Cellia. If the author
of a classification finds it difficult to place specimens in their correct
genera it is scarcely to be expected that the medical man in the
tropics will be able to do so, and, as a matter of fact, the method
which most workers in the tropics — and, so far as we have been
able to ascertain, most entomologists — who desire to follow Mr.
Theobald's classification of "anopheles" adopt, is first to ascertain
the specific name of the specimen and then to refer to Mr. Theobald's
synoptic table for the generic name. This shows that the differ-
ences between the different species are more marked and more
easily found out than are the differences between the various
genera — a fact which is opposed to all the principles of classifica-
tion. In view of these difficulties we are somewhat surprised to
see that authors who have recently written upon methods for
the study of tropical diseases, have adopted without question the
many new genera which Mr. Theobald has created ; but we
find some consolation in thinking that in doing so they have
been influenced rather by the fear lest their books may not be con-
sidered up-to-date than by their own personal opinions on the
matter. In the preface to the second edition of his book on
mosquitoes, Colonel Giles frankly admits that he has followed
implicitly Mr. Theobald's monograph, and says : " It must be
understood that I merely reproduce, and desire to imply no
personal opinion as to the justness or otherwise of the conclusions
involved." Drs. Stephens and Christophers in their book on
the practical study of malaria, and Dr. Daniels in his book
entitled " Laboratory Studies in Tropical Medicine," have also
merely reproduced Mr. Theobald's synoptic table of the Ano-
phelina, and have not attempted to explain how the different
o-enera under which these insects are placed may be distin-
guished from one another by anyone who has not the type-insects
before him.

[65

The importance of habits, &c.

Lastly, it is not difficult to show that Mr. Theobald's method
of classification does not bring species which are alike in habits and
pathological significance, into the same groups. No two mosquitoes,
for example, are more unlike each other than rossi and culicifacies.
The former can be recognised at a glance as a typical " anopheles,"
the latter looks very like a small brown " culex " ; the former breeds
exclusively in rain-formed puddles near houses, the latter is one of
the typically stream breeding species ; the former, though so abun-
dant, is scarcely, if at all, concerned in the spread of malaria, while
the latter is perhaps the most active agent in the spread of this
disease in India. When we consider further that the seasonal pre-
valence of these two species, at any rate in the Punjab, does not
correspond, and that their larvae and eggs have entirely different
characters, we may well ask ourselves whether a classification
is correct which places these two species in the same genus
(Myzomyia), while two mosquitoes, which resemble each other so
closely in their adult and larval states, in their habits, and in their
pathological significance, as listoni and jeyporiensis, are placed
in different genera (Myzomyia and Pyretophorus).

After a consideration of the facts which we have attempted
to outline above, we have decided, until further study of ''an-
opheles " mosquitoes under natural conditions has been made, to
classify these insects only into groups containing closely allied
forms. Under each group we have described and illustrated
two or more fairly constant types, which we are inclined to
regard rather in the light of sub-species or varieties than true
species. In defining the groups we have not been guided by any
one character (as the scale structure of the adults, for example), but
have considered the structure, colour markings, and habits of the
adults, the structure arid habits of the larva and pupa, and
the general appearances of the eggs. In each group, however,
members are met with which partake of some of the characters
of one group and of some of another, and these individuals act
as the connecting links between the different groups. We believe
that the most typical member of each group probably represents
a true species, while the other members constitute sub-species
or varieties, but whether this is so or not, the arrangement will
doubtless simplify matters considerably for medical men in the

66]

Classification into groups containing closely allied forms.

tropics. By placing individuals with similar characteristics in
groups the difficulties of deciding whether two individuals really
belong to distinct species are, to a great extent, overcome ; for the
general appearance, habits, and above all the pathological signifi-
cance of the species of each group are the same, and for those who
are unable to undertake the minute examination necessary to
accurately determine the species, it is of some advantage to
determine the group to which any specimen belongs. If two
individuals such as listoni and funestus, for example, are alike
in their general characters, in their habits and breeding places, and
in their power of carrying malaria or other tropical disease, it is
really unnecessary, except from a purely entomological point of
view, to separate them as distinct species. The object of the worker
on tropical diseases is to separate into distinct genera and species
only those insects which, from some marked difference in habits,
or from any other reason, exert a different influence on any tropical
disease. If, for example, it were proved that all " anopheles" mos-
quitoes were alike in habits and in their power of carrying malaria,
the tropical worker would have little object in separating them
even into different species : it would be sufficient for him to study
" anopheles" mosquitoes as a whole. It is known, however, that the
habits of different species differ markedly, and, for this reason, their
influence on the spread of disease must be different. A species
which habitually lives and finds its food apart from man cannot
have the same influence on the prevalence of malaria as a species
which is always found near human dwellings. In any rational
classification of " anopheles," therefore, the question of habits in
nature is a very important one — of more importance, we think, than
a slight, though constant, structural difference in any one stage
of the insect's life.

We have accordingly divided the Indian " anopheles" into ten
groups.

GROUP I.

The "anopheles" of this group are, as a rule, large black mos-
quitoes with long spidery legs. The wings are marked with two
minute yellow or white spots on the costal border. Very many
varieties occur among the mosquitoes of this group, to which
many names have been given. We have described two types,

Group I.

viz. : — A. barbirostris, which has entirely black palpi and very broad
spindle-shaped scales, and A. nigerrimus, which has four bands on the
palpi and less broadly spindle shaped scales. These two represent
the common types of these mosquitoes in India. The larvae of thk
group are very characteristic and can readily be distinguished from
all other "anopheles" larvae. The external frontal hairs have a brush-
like appearance forming the so-called " cockades." The antennae
have a large branching hair on their inner sides. The pupa is also
characteristic (as was first pointed out by Cogill) and can readily
be distinguished by the shape of the breathing horns. The tube,
before expansion, arches up over the dorsum of the thorax almost
meeting that of the opposite side in the middle line, and is then
bent on itself at right angles to the dorso-ventral plane of the pupa,
thereby becoming inverted U shaped. The tube at its outer ex-
tremity expands into a cavity, somewhat resembling the shape of
an open mussel shell. The enveloping membrane of the eggs
of the mosquitoes of this group consists of a layer of cells of
extremely regular hexagonal outline more regular than in the eggs
of any other " anopheles."

Breeding places. — The larvae are generally found separately
or scantily in pools overgrown with weed, hence tanks are common
breeding grounds.

Observation. — This group is practically Theobald's genus
Myzorrhynchus.

We have retained the name nigerrimus, although the description
given under that name of the type specimen in the British Museum
in Theobald's " Culicidae of the World," Vol. I, page 145, does not
quite correspond with the specimens we have found in India ;
indeed we have never noted a specimen with black tips to the palpi.
Our type most nearly corresponds with Theobald's description of
Myzorrhynchus minutus, but our drawing was made from a very large
specimen, one of the largest " anopheles" we have seen ; the name
minutus would therefore be misleading.

The following recorded species in other countries than India
belong to this group : — umbrosus (Theobald), albotaeniatus (Theo-
bald), sinensis (Wiedmann), malayensis (Theobald), pseudopictus
(Grassi), mauritianu* (Grandprej, paludis (Theobald), tenebrosus
(Donitz), bancroftii (Giles).

68]

Groups II, ///, IV.

GROUP II.

This group includes moderately large mosquitoes, in scale struc-
ture approximating to the above group, i.e., with long white and
golden hair-like scales on the thorax, the wing scales spindle-shaped,
not so broad as in nigerrimus. It includes elegans and punctulatus.
The only specimens of this group, so far as we are aware, collected
in India, were taken by Dr. Cogill in Karwar. Dr. Donitz has
found species of this group in Sumatra and Borneo.

Habits and character of the larva. — The larvae of elegans were
found, when water was abundant, in the open, but, as a rule, they
were found in jungle springs. The larva has simple unbranched
frontal hairs, and well developed palmate hairs.

Observations. — Little is known of this group. It may be
remarked that in many characters rossi approximates to this group,
e.g., in the character of the scales and hairs on the thorax and
abdomen, and in some of the larval characters and habits, but the
wing scales of this group are considerably broader and somewhat
shorter than in rossi.

GROUP III.

This group includes at least two known Indian species, pul-
cherrimus and ivillmori. Probably also Stephens* should be included
in this group ; it has, however, been classed with rossi in a separate
group because of its similar habits and its marked association with
human habitations.

The mosquitoes of this group are very beautiful and are covered
with broad white and dark brown scales on the thorax, abdomen and
wings. They are comparatively rare and little is known of their
habits ; they are at once recognised by their very scaly structure.
The larvae have been found in clear pools of water ; those of pulcher-
rimus have the median frontal hairs simple, while the external angu-
lar are branched.

GROUP IV.

This is a large group of black and white mosquitoes, the majority
of which have one or more tarsal segments of the hind legs white.
The larvae have well developed palmate hairs ; each leaflet, as a rule,
has a well-marked blade and rather a short terminal filament. The
frontal hairs are more or less branched, most branched in fuligmosus

Groups IV, V.

which most closely approaches nigerrimus in its structure and habits,
and practically simple and unbranched in the case of theobaldi and
maculatus which in their habits ( being for the most part stream
breeders ) most closely approach the next group.

The larvae of the majority of the members of this group are
found in deep green pools, tanks, lakes, etc., but maculatus and theo-
baldi are frequently found in streams. The shape of the eggs of
this group vary considerably, but the majority have rather a narrow
deck surface, and the lateral floats encroach upon this surface — that
is, they are placed high up on the sides of the egg.

Observations. — Certain seasonal variations have been noted in
Juliginosus which so alter the appearance of this mosquito that
the winter form might have been considered as a distinct species
on as good grounds as those upon which some species are at present
differentiated from one another.

There can be little doubt that some of the types we have de-
scribed may be shown simply to be a seasonal, geographical, or other
variation of some other type.

We would specially draw attention in this connection to theo-
baldi and maculatus, which seem to have distinct and separate geo-
graphical distributions.

A. fuliginosus is the only member of this group which has, up
to the present, been found infected in nature with sporozoites resem-
bling those of malaria.

GROUP V.

This is by far the most important group of "anopheles" because
of the marked malaria-carrying powers of its members. They have
frequently been found infected with sporozoites in nature and are, as
a rule, abundantly found in all notoriously malaria-infected localities.
They are all rather small, very dark mosquitoes, and when resting
on any surface they are very difficult to detect.

These mosquitoes are typical stream breeders, but culicifacies
can accommodate itself to almost still water. The larvse have simple
unbranched frontal hairs, except in the case of jeyporiensis which
has branched frontal hairs. Palmate hairs are present on all the
abdominal segments except the eighth, and a pair also is found on
the thorax. These hairs are very large and well developed in all
except culicifacies.

70]

Groups V,

Observations. — The breeding places of these mosquitoes deserve
special attention, for they are the most important malaria-carrying
anopheles and their larvae are generally overlooked by the so-called
" mosquito brigades." Paraffin oil, as a rule, will not affect them.
The little streamlets and irrigation canals in which they occur
are generally passed over with the remark " larvae could not
breed here, the water is flowing too rapidly." This certainly is
not the case ; in the little quiet eddies by the side of such streams
the Iarva3 can usually be taken after patient fishing with a
white saucer or net. Hardly any natural stream, because of the
side eddies and grassy edges, flows too rapidly to afford shelter
for these larvas.

The three types we have described in this group are fairly
constant, but individuals are frequently met with, which possess some
of the characters of one type, some of another. Some of these
variations have been mentioned under the description of each type.
To this group belong the majority of the mosquitoes classed by Mr.
Theobald in his genus Myzomyia. In addition to the types we
have described, Theobald's albirostris, funesta, rhodexiensis and
leptomeres undoubtedly belong to this group. Some remarks have
already been made on the probable identity of some of these species
with the types we have described.

GROUP VI.

This group includes two very distinct species, viz., rossi and
stephensi, which have been classed together more on account of
their habits than because of any structural relation. Superficially
the two species very closely resemble one another, but structurally
they are very distinct. They are placed here because of their very
intimate connection with man, for they are never found far from
human habitations, and are, as a rule, the most common "anopheles"
found in India. They are typically "domestic" species, for they
are readily captured in almost any house in India at a suitable
season. But, despite these facts, they appear to play a very minor
part in the propagation of malaria. Large numbers, especially of
A. rossi, have been caught even in markedly infected houses (where
anopheles of group V were shown to be infected) and on dissec-
tion have been found to be uninfected.

[71

Groups VI, VII, VIII.

These mosquitoes are of moderate size and of a light brown
colour. Their colour permits them to be readily seen on any dark
surface on which they rest. The larvae are, for the most part,
found in puddles, shallow pools, and pots. They have simple un-
branched frontal hairs. The eggs have a broad " deck " surface,
the floats are placed rather low down in rossi and higher up in
stephensi, so that in the latter the deck area is encroached upon.

Observations. — The mosquitoes of this group contrast with
those of group V in being light coloured and therefore readily seen
and caught ; they breed in still water ; and probably play little
part in the propagation of malaria, although intimately connected
with man. Under the detailed description of each mosquito will be
found arguments for placing rossi near to punctulatus and stephensi
near to willmori. The close \ resemblance of rossi to costalis of
Africa, both in structure and habits, is noteworthy.

GROUP VII.

In this group at present we can class only one Indian mosquito,
viz., turkhudi. This mosquito in the scale structure of the adult
approaches closely to group V and has been classed by Theobald
in his genus Myzomyia. It differs, however, from all other Indian
anopheles (except nagpori, a single specimen of which alone has
been taken) in having the tips of the palpi black, although there
are three light bands on the palpi. The larval and egg characters
too contrast markedly with other ' 'anopheles." Turkhudi is a large
brown mosquito with characteristic long thin palpi. The larvae are
always found in still water, chiefly by the side of river-beds in the
pools formed in the soft mud by the feet of cattle. The larva has
simple unbranched frontal hairs, and an additional hair is also found
overhanging the mouth. The palmate hairs are small and
badly developed, and found only on a few of the abdominal
segments, hence the larva does not lie quite flat on the surface
of the water like an ordinary ' 'anopheles." The eggs are peculiar
in that the floats are practically absent.

GROUP VIII.

The two mosquitoes included in this group, viz., gigas and
lindesayi, have been found only in the hills. Little is known of their
life-history or habits.

72]

Groups IX, X.

GKOUP IX.

This group at present contains only one Indian species, viz.,
aitkeni. It has unspotted wings and assumes a " culex-like "
attitude when at rest. For these reasons is very liable to be mis-
taken for a " culex." Details of its larva will be found under the
description of the mosquito in Part II.

GROUP X.

This group also contains a single mosquito A. culiciformis. It
has unspotted wings like the above, and is even more "culex-like" in
its attitude and appearance. Certain structural characters of this
mosquito, both in its adult and larval form, are so distinct and
different from any other " anopheles" as to be of undoubted generic
value. For details the reader is referred to the description in
Part II.

[73

PART II.

SYSTEMATIC DESCRIPTIONS

OF THE

ANOPHELES MOSQUITOES

FOUND IN INDIA.

GROUP I.

Types : — .4. barbirostris and ,4. nigerrimus.

1. ANOPHELES BARBIROSTRIS (Van der Wulp).

(Coloured Plate II. Plate V, Fig. 1. Plate X, Fig. 1.)

References :— Leyden Museum Notes VI, p. 48; Theobald, Mon. Colic., Vol. I, p. 146,

Vol. Ill, p. 86 ; Db'nitz, Zeitschrift f. Hyg. XLIII, p. 227 ; Giles, Handbook Mosq.,

2nd Ed., p. 308, and Rev. of Anoph., p. 39.

Synonym, Myzorhynchus barbirostris (Theobald).

JHIS is a large mosquito very easily recognised by
its thick black unbanded palpi and dark wings.

Palpi entirely black and covered with large,
broad, black scales.

The proboscis is in like manner thickly covered
with dark scales.

The head is for the most part covered with black upright
forked scales ; some white scales occur on the occiput, and there
is a prominent frontal tuft of white hairs. The dorsal and lateral
aspects of the thorax are covered with brown and black hairs and
hair-like scales.

The abdomen is of a dark purple colour, and is covered
with many hairs. A few white scales are present on the ventral
surface of some of the segments, and on the venter of the last
segment there is a tuft of black scales.

The wing veins are thickly covered with large broad spindle-
shaped scales. (PL X, Fig. 1.)

[77

Anopheles barbirostris.

The costa is almost entirely black, save for a few white scales
at its distal extremity, and a few at the junction of the outer and
middle-third of its course.*

The first lono- vein has a few white scales near its commence-

o

ment, and again a few at the situation of the inner spot on the costa.

The second long vein is entirely dark scaled, except for two
small patches of white scales on its posterior branch.

The third long vein is mainly covered with dark scales, but the
dark scales are interrupted here and there throughout the length
of the vein by a few white scales.

The fourth long vein is dark-scaled on the main trunk, but the

o

dark scales are mingled with light scales on both anterior and
posterior branches.

The fifth long vein is irregularly covered with dark and light
scales ; the light scales only predominate at two points on each
branch of this vein, forming here distinct light spots.

The sixth long vein shows two distinct white-scaled spots, one
near the middle of the vein, another near its termination.

The wing fringe is for the most part dark, but there is a light
distinct spot at the apex of the wing, and another opposite the
extremity of the posterior branch of the fifth long vein.

The legs are of a dark brown colour, and have light scales
at all the joints. None of the hind tarsal segments are white in
their whole length.

Characters of the larva. — PL V, fig. 1. The larvae of this
species are easily identified by the naked eye from their large size,
black colour, and the fact that when resting at the surface of the
water they are nearly always bent more or less in the shape of an S.
Their microscopical characters are shown in the figure. The
external frontal hairs are converted into a large tuft or '< cocade,"
which is easily seen projecting from the front of the head. On the
inner side of each antenna is a large branching hair.

* The reader is strongly advised to refer constantly to the coloured plates when
going through the descriptions of the markings on the palpi, wings, and legs of the
different species. He will obtain little profit from merely reading the descriptions, and,
unless he carefully follows out on the coloured plates the markings that are described in
the text, he will find the subject very confusing and uninteresting. The beginner may,
at this stage, derive some help from a second reading of pages 28 to 33, and the table on
page 32 should be kept constantly in mind.

78]

FIG. 2.

;

A.

B.

PLATE V. Fig. /.—The larva of A. iMrblrostris. A.— General view; B.— The frontal hairs maernined ; C.— A palmate hair magni-
fied ; D.- The branching hair on the inner-side of the antenna of A. barbirostrf* larva. Fig. 2.— The larva »of A. fl&ffHWttu.
A, — General view ; B.— The frontal hairs magnified : ^.— A palmate hair magnified.

Anopheles nigerritnus.

Habitat and observations. — This species occurs in the outskirts
of Calcutta and in several places in the plains of Bengal, in the
Central Provinces, in the Punjab (Lahore), in Assam, and in the
South of India. It has also been met with in Bombay and many
other parts of India where suitable breeding grounds are present.
Outside India it occurs in Burmah, the Straits Settlements and the
Malay States. Its larvae are usually found in deep dark pools with
much vegetation. In Lahore they occur in the lily ponds of the
public gardens. Tanks overgrown with green weed are also favorite
breeding grounds. It has been shown that, under experimental
conditions, human malaria parasites can develop in this species,
but it is doubtful whether it ever acts as a carrier in nature owing
to its rarity in houses.

2. ANOPHELES NIGERRIMUS (Giles).
Coloured Plate III.

References :— Giles, Handbook Mosq., 1900, p. 161 ; 2nd Ed., p. 306, and Rev. of Anoph.,
p. 38 ; Theobald, Monog. Culicid., Vol. I, p. 150 ; Donitz, Zeit. f . Hyg., XLTII, p. 228.

Synonym, Myzorhynchus minutus (Theobald).

This is a dark brown mosquito with thick palpi and rather
light wings, somewhat resembling A. barbirostris.

Palpi with four light bands. The tips of the palpi are white,
then come a few dark scales, then again another light-scaled band.
The remaining two light bands occur at the joints between the
fourth and third, and third and second, segments of each palp.
There are also some light scales mingled with the dark scales on
the second segments of the palpi.

The proboscis is covered with dark scales except at its tip which
is of a yellowish white colour.

The head is covered with black and white upright scales, the
former predominating on the nape, the latter on the occiput. There
is a well-marked frontal tuft of white hairs.

The dorsal surface of the meso-thorax is covered with light
brown and white scales and hairs.

The abdomen is covered with light brown hairs, and there are
a few scales on its posterior extremity.

The veins of the wings are covered with broad spindle-shaped
scales, not so broad, however, as those found on A. barbirostris.

[79

Anopheles nigerrimus.

The costa is for the most part black, but there are three minute
white spots in the outer third of its course ; one of these spots is
situated at the junction of the outer and middle third of the costa,
another at its distal extremity ; the third and largest white spot
lies close to the distal extremity, separated from the distal white
spot by a few dark scales.

The first long vein is covered with light and dark scales, two
indistinct large light spots, where the light scales predominate over
the black scales, are found, one near the middle of the vein, another
in its inner third. There is a distinct light spot opposite the largest
white spot on the costa, and the outer extremity of this vein has
a few white scales.

The second longitudinal vein, like the first, is covered with a
mixture of dark and light scales, the latter predominate opposite
the middle light spot of the first long vein and extend to the
bifurcation of the vein. There are light scales forming indistinct
spots on each of the branches of the vein.

The third long vein is for the most part covered with light
scales, except at its origin and termination.

The fourth long vein is covered with light and dark scales
almost evenly intermixed throughout the course of the vein, except
near its origin and at the termination of its branches, where black
scales are most numerous.

The fifth long vein has black scales at its origin, but white
scales predominate throughout the rest of the course of the vein
and its branches ; the extreme tips of the anterior and posterior
branches of this vein have black scales

The sixth long vein is mostly light-scaled, but there are two
dark-sealed spots on this vein.

The wing fringe is dark-scaled except at the apex of the wing.

The legs are of a dark-brown colour, but there are light scales
at all the joints. None of the hind tarsal segments are white in
their whole length.

Variations in the details of the markings on the wing field are
frequent, but the two light spots on the costa as well as the apical
spot are constant.

The wing fringe is, as a rule, uninterrupted by light scales,
but it is not uncommon to find a few opposite some of the long

80]

Anopheles nigerrimus.

veins, especially opposite the anterior and posterior branches of the
fifth long vein.

Characters of the larva.— The larva of A. nigerrimus resembles
that of A. barbirostris very closely. The median frontal hairs
are unbranched but may be bifurcated at their extremities. The
external frontal hairs are very much branched, so that they form
distinct " cocades " in front of the whorl organs. The antennae
possess a large branching hair on their inner side as in the larva of
A. barbirostris. Palmate hairs are borne by the second to the
fifth abdominal segments.

Habitat and observations. — This is a fairly common species in
the outskirts of Calcutta and in other places in the plains of
Bengal. It also occurs in Travancore and in the Madras and

o

Bombay Presidencies.

It has been shown that the embryos of " Filaria Bancroft! "
can develop in this species as well as in A. rosti. Its larvae are
usually found in deep shady pools, containing grass and water weed,
at some distance from habitations, and the adults are seldom met
with in houses.

A large number of species closely resembling ,4. nigerrimus
have been described, but it is very probable that the majority are
only varieties (or perhaps representatives of local races or sub-
species) of a single type. The following forms are described as
distinct species by Mr. Theobald : — vanus, sinensis, rninutus,
indiensis, fiseudopictus, and alboannulatus. A. vanus is recorded as
occurring in Travancore, A. minutus in Lahore, and A. indiensis
in Madras. According to Colonel Giles, who has apparently examin-
ed the single specimen of A minutus in the British Museum,
its only difference from other members of the "sinensis group"
is the fact that the wing spots are white instead of yellow — a
distinction which, of course, is no value. Between A. alboannulatus
and A. vanus, Colonel Giles cannot detect any difference ; and A.
indiensis, differs from vanus only in a detail of wing venation —
a character which has been shown to be very variable.

[8

Anopheles leucophyrus.

GROUP II.

Types : — A. leucophyrus and A. punctulatus.

3. ANOPHELES LEUCOPHYRCS (Donitz).
Figures facing page 83 and in text. Plate IX, Fig. 4.

References: — Donitz, Insect. Borse, January, 1901, p. 37 ; Theobald, Monog. Culicid.,
Vol. HI, p. 51 ; Giles, Handbook Mosq., 2nd Ed., p. 312.

Synonyms, Anopheles elegans (James).
Myzomyia, elegans (Theobald).

The specimens which we now regard as a variety of A. leuco-
phyrus (Donitz) are described in Mr. Theobald's monograph as a
separate species under our manuscript name elegans. Mr. Theobald
places it in the genus Myzomyia, but is not sure whether it ought
not to be classed in the genus Nyssorhynchus, in which case — unless
mosquitoes can produce varieties belonging to different genera — it
cannot be a variety of leucophyrus as he says is possible and as
appears to us to be very probable. The following is our description
of this species :

A dark mosquito, the wing veins of which are thickly clothed
with rather broad spindle-shaped black and white scales, which form
numerous small spots on the wing field, so that the wing has a
beaded or mottled appearance. Legs thickly mottled with black
and white scales. Palpi with four white bands. Abdomen with
long golden hairs but no scales. Thorax with long narrow whitish
scales and hairs.

Palpi with four white rather narrow bands. A few white
scales are present on the bases of the palpi ; tips of the palpi white.*

Proboscis brown with a lighter tip.

Head with broad white forked scales in front and dark ones
behind, with a scanty tuft of long white hairs projecting forwards.

Antennae brown with white hairs.

Thorax chiefly, covered with white hairs, but also with a few
spindle-shaped creamy scales. Dark longitudinal lines and two
dark eye-like spots can be made out on the dorsum of the thorax.

Halteres with the knobs covered with creamy white scales.

* i. e., the outermost of the four white bands on each palp includes the tip.
82]

PLATE XII.

A. Leucophyru.8 var. Elegants.

' XI J. Anopheles Imcopkyrtu variety elegant.

Anopheles leucophyrus.

Abdomen black, thickly covered with golden hairs but with-
out scales. A very marked golden apical tuft of hairs.

Wing veins covered with rather broad scales forming numerous
black and white spots arranged as follows : — The costa shows four
large black-scaled areas and three (sometimes only two) small ones ;
the first longitudinal vein shows seven dark-scaled areas of different
sizes arranged as shown in the diagram ; the main stem of the
second longitudinal vein has three black-scaled areas, the anterior
branch has three spots and the posterior three ; the third longitudinal
vein has seven (sometimes only six) small black areas ; the fourth
longitudinal vein has three large black areas on its main stem and
generally three on each of its branches ; the fifth longitudinal
vein has four dark spots on its main stem and one at its bifur-
cation, its anterior branch has five dark areas and its posterior
four ; the sixth longitudinal vein has four or five (sometimes six)
dark areas.

As will be seen from the accompanying drawing of the wing of
another specimen, the number of dark and light-scaled areas on
some of the veins is not constant, and two or three of the small
spots may sometimes be joined together so as to form one long dark-
scaled area.

The wing fringe is interrupted by a light-scaled area at the
termination of each of the longitudinal veins.

The legs are speckled with white scales on a brown ground ;
in the fore legs the fifth tarsal segment has a few white scales at its
tip, and there are apical white scales which extend over the joint so
as to form a band to each of the other tarsal segments. The first
tarsal segment is speckled with white scales in addition to the
apical banding, and the tibia and femur are also speckled. The

[83

Anopheles punctiilatus.

markings of the mid legs are the same as those of the fore legs. In
the hind legs (see figure) the femora and tibiae are speckled with
white scales. At the lower end of the tibia and the upper end of
the first tarsal segment (metatarsus) there are broad white bands,
the two together forming a very broad and characteristic band at
this joint ; at the other tarsal joints also there are white bands.
The tip of the fifth tarsal segment has a few white scales. None
of the tarsal segments are wholly white.

Characters of the lance. — The larvae of this species were found by
Dr. Cogill "in pools in the open while water was abundant, but
as a rule in jungle springs, and it was particularly partial to water
containing decaying leaves. " The larva has simple unbranched
frontal hairs and well-developed palmate hairs on the first seven
abdominal segments. The terminal filaments of the palmafce hairs
are rather short (see figure).

Habitat — Bred from larvae by Dr. Cogill in Karwar. The
adults were never found in houses.

4. ANOPHELES PUNCTTJLATUS (Donitz).
(Figure facing page 85).

References: — Insecten Borse, January 1901, p. 37; Theobald, Monog. Culicid.,

Vol. I, p. 175.

Synonym, Myzomyia, punctulatus (Theobald).

A large mosquito with the wing veins thickly clothed with
rather broad spindle-shaped black and white scales forming very
numerous dark and light spots on the wing field ; palpi mostly
white scaled and with speckled legs, the terminal segments of the
hind legs being entirely black.

The head with the usual scale characters and with a white
frontal tuft.

Palpi with four broad white bands. The anterior half of each
palp is practically white, but it has two narrow black bands which
divide it into three white scaled portions, The posterior half of
each palp is mostly black-scaled, but divided into two by a narrow
light- scaled band. A few white scales also occur on the dorsal
surface of each palp near the base.

Thorax covered with golden brown and white hair-like scales
and hairs.

84]

PLATE XL

PLATE XI. Anopheles punctulutus.

Anopheles fomctulatus.

Abdomen thickly covered with golden hairs, especially accumu-
lated at the posterior extremity, forming a brilliant yellow termina-
tion to the abdomen. \

Wings much spotted, the veins clothed with rather broad
spindle-shaped scales. The costa has seven dark areas separated
by white-scaled portions increasing in size from base to apex.
Apex of wing white-scaled ; base black-scaled.

The first longitudinal vein has black-scaled areas opposite the
five outermost on the costa, but the area opposite the middle
and largest costal spot is divided on the first longitudinal into three
by two small white-scaled spots.

The second longitudinal vein has a long black-scaled area at its
commencement and two other minute black- scaled portions before
it divides ; each branch of this vein has four or five dark-scaled
portions.

The third longitudinal vein has many minute dark-scaled spots.

The fourth longitudinal vein at its inner third is chiefly light-
scaled, its middle third is chiefly black-scaled, while its branches
have each two or three dark-scaled portions.

The fifth and sixth veins have small alternate areas of black
and white scales.

The wing fringe is light scaled at the apex and to the level
of the third long vein, thereafter it is dark-scaled except where it is
interrupted by light scales at the terminations of the long veins.

The legs have the tibia? and femora speckled and white scales
at the apex of all the segments except the two terminal segments of
the tarsus.

Habitat and observations. — This mosquito very closely resem-
bles A. leucophyrus and may be a seasonal variety of that species.
It was found in Dr. Cogill's house in Karwar during the rains
only, while leucophyrus was bred by him from larva? in the cold
weather. The larvae of punctulatus were not found. Dr. Cogill
remarks that in punctulatus the supernumerary cross vein is op-
posite to the mid cross vein, while in leucophyrus the mid cross
vein is internal to the supernumerary cross vein.*

A single specimen of A. punctulatus was taken in a house
at Parel near Bombay, in August. Outside India it occurs in the
Straits Settlements, in Sumatra and in Borneo.

* Our specimens show that this character is not constant (see figures).

[85

Anopheles pule her rimus.

GKOUP III.

Types : — A. pulcherrimus and A. willmori.

5. ANOPHELES PULCHEBRIMUS.
Coloured Plate IV, Plate IX, Fig. 6.

References .-—Theobald, Proc. Roy. Soc., Vol. LXIX, 1902, p. 369, and Monog. Culicid.,
Vol. Ill, p. 107. Synonym, Cellia Pulcherrima (Theobald).

This species may be taken as the type of a group of species
characterised especially by the fact that the abdomen is thickly
scaled, the scales forming distinct tufts at the sides of each segment.

The palpi are equal in length to the proboscis and are densely-
scaled. The tips of the palpi are white and each has four white
bands. The terminal band includes the tip and is separated from
the next by only a few black scales : the remaining white bands are
at the joints between the third and fourth, and the second and third
segments of the palpi. In addition to the bands the palpi are
speckled with many white and brown scales.

The proboscis, which is also covered with scales, especially
near its base, is brown with a white tip.

The head is densely covered with dark brown and white scales,
and a well marked frontal tuft of white hairs projects forwards ; the
antennae are brown with white bands and white hairs at each joint.

The thorax is covered with broad silvery-white scales inserted
on a dark brown ground and interspersed with white hairs ; the
pleurae are also densely scaled.

The scutellum is tri-lobed and more or less covered with silvery
scales ; the metanotum is dark brown.

The halteres are yellowish brown and their lobes carry a
number of small silvery scales.

The abdomen is thickly covered with silvery white scales and
golden hairs ; the scales are flat and broad. Projecting laterally
from the apex of each segment is a tuft of dark brown scales.

The wing veins are covered with large broad scales of brown
and white colour, the latter predominating ; the costa shows four
prominent dark-scaled areas and two smaller dark spots ; the first
longitudinal vein has dark-scaled areas corresponding with the four
large dark areas on the costa, but the second dark area is divided

86]

FIG. 1.

FIG. 2.

c c

PLATE VI. Fig. /.—The larva of A. rogsi. A— General view; 5.— Frontal hairs magnified ; C.— A palmate hair magnified.
Via. 2. -The larva of A. stenliensi. A.— General view ; B — Frontal hairs : C.— A palmate hair.

Anopheles pulcherrimns .

into three by two collections of white scales ; the main stem of the
second longitudinal vein is white-scaled ; on its anterior branch
there are two dark-scaled spots corresponding with the outer two
on the costa ; on its posterior branch there are also two small spots ;
the third longitudinal vein is white-scaled throughout except for a
few black scales near its origin and termination ; the fourth longi-
tudinal vein has black scales at its bifurcation, and there are two
small black-scaled spots on each of its branches ; the fifth longitu-
dinal vein has a single dark-scaled patch on its main trunk, three
black-scaled areas on its anterior, and one on its posterior branch ;
the sixth longitudinal vein has three small black-scaled spots.

The wing fringe is interrupted by light-scaled areas at the
terminations of all the long veins and by a long area on the inner
fourth of its course.

The legs are covered with brown and white scales ; the fore legs
have the femora and tibiae white on their under surfaces and speckled
with brown scales on their upper surfaces ; the tarsal segments,
except the fourth and fifth, have apical white bands ; in the mid legs
the femora have a large white patch near their apices ; the tibiae
and tarsal segments, except the fourth and fifth, have apical white
bands ; the femora of the hind legs have also a white patch near
their apices and the last 3f hind tarsal segments are pure white.

The palpi of the male have five broad, almost equal, white bands
separated from one another by very narrow bands of black scales.
The other markings do not differ materially from those of the
female.

Characters of the eggs and larvce. — The eggs are of the same
type as those of A. rossi. The larvse have the median pair
of frontal hairs simple and the external pair branched. Palmate
hairs are present from the second to the seventh abdominal
segments, and the terminal filaments of the leaflets are long.

Habitat and observations. — This is a somewhat rare species.
It occurs with a limited seasonal prevalence in the Punjab (Lahore,
Meean Mir, Ferozepore). In Meean Mir it was found in small
numbers in the barracks of the native troops and in outhouses of
the native bazaars, and in September its larvae were found in an
overflow pool of an irrigation watercourse. During the winter a few
adult specimens were found in a village near Lahore, and it appears

[87

Anopheles willmori.

to be one of the few species which can tide over the Punjab winter
in the adult condition. It has recently been found to occur in Goa
in the Bombay Presidency.

6. ANOPHELES WILLMORI (James).

Reference .-—Theobald, Monog. Culicid., Vol. Ill, p. 100.
Synonym, Nyssorhynchus Willmori (Theobald).

Palpi with three white bands. Thorax dark brown, covered
with white scales and hairs. Abdomen brown with many golden
scales and hairs. Legs deep brown thickly speckled with white ;
the last tarsal segment of the hind leg pure white. Wings spotted.

Head black with some upright white scales ; antennae light
brown with white hairs ; palpi scaled and with three white bands,
the two terminal of which are equal and broad and the third
narrow ; proboscis dark brown.

Thorax dark brown covered with white scales and a few hairs ;
pleurae black ; scutellum with a few white scales and long bristles.

Abdomen deep brown, with many golden hairs and scales-
the scales and hairs on the last segment are very closely packed
together, so that this segment is almost entirely of a golden brown
colour ; some of the scales which project from the sides and
termination of this segment are dark brown in colour.

The halteres carry a number of short thick scales. Legs
dark brown thickly speckled with white spots ; in the fore and
mid legs there are apical white bands to the femora, tibiae and to
all the tarsal segments except the fourth and fifth ; the femora,
tibiae and the first and second tarsal segments are brilliantly marked
with bands and patches of white scales ; the apical banding of the
first, second and third tarsal segments extends over the joint to the
base of the next segment. In the hind legs the femora, tibiae and first
tarsal segment are thickly speckled with white patches ; the tibia
and first tarsal segment have apical white bands, and the second,
third and fourth tarsal segments have both apical and basal bands ;
the last tarsal segment is wholly white.

The wing veins are clothed with black and white scales ; the
costa shows four large and three small black areas, the latter being
near the base of the wing ; the first longitudinal vein has four

PLATE XIV.

rr~

A . Karwari

PLATE XIV, Anopheles kanvari ; showing the markings on the palpi and hind leg,
and the head of the larva.

Anopheles karwari.

black spots corresponding to the large areas on the costa ; the
second longitudinal vein has three small dark spots on its main
stem and two on each of its branches ; the third longitudinal vein
is white-scaled except for a small dark spot at its commencement
and another at its termination ; the fourth longitudinal vein has
three dark-scaled areas on its main stem and two on each of its
branches ; the fifth longitudinal vein has a small spot at its
commencement, two spots on its anterior branch and one on its
posterior ; the sixth longitudinal vein has three small dark spots.
The wing fringe is interrupted by light- scaled areas at the termina-
tions of all the longitudinal veins.

Habitat and observations. — Collected by Lieutenant Willmore,
I.M.S., in Kashmir. Its larvae were found in a small clear puddle
formed by a spring at a height of 4,800 feet.

It differs from J. stephensi in its abdomen being more thickly
scaled and having fewer hairs, as well as in the wing markings and
in having the terminal segment of the hind tarsus pure white.

From A. maculatus (Theobald) it differs in having a thickly-
scaled abdomen.

GROUP IV.

Types : — A. karwari, A. fuliginosux, A. jamesi, A. maculipalpis,
A. theobaldi and A. maculatus.

7. ANOPHELES KARWARI (James).

Reference .—Theobald, Monog. Culicid , Vol. Ill, p. 102.
Synonym, Nysaorhynchus Karwan (Theobald).

Palpi with four white bands. Thorax covered with snowy
white scales and some hairs ; abdomen thickly clothed with golden
hairs and with some scales on the last two segments. Legs not
speckled ; the terminal tarsal segment of the hind legs pure white.

Head with white upright forked scales in front and dark
ones behind ; a small tuft of white hairs projecting forwards from
the head.

Palpi thickly clothed with scales and marked with four white
bands ; tips of the palpi white ; the two terminal bands are broad
and equal, the other two are narrow, (See figure.)

[89

Anopheles karwari.

Antennae black with silvery hairs.

Thorax black, covered with numerous snowy white spindle-
shaped scales on its dorsal aspect. Three longitudinal dark lines
devoid of scales can be made out on the dorsum as well as a lateral
eye-like bare spot on each side and a median bare spot posteriorly.
Pleurae black with two indistinct longitudinal white lines on each
side.

Scutellum with some scales like those on the thorax and with
bristles.

Abdomen black, thickly clothed with golden hairs ; on the last
two segments the hairs are very dense, and a number of scales are
also present on these segments, those which project from the sides
of the segments being dark coloured and the others golden brown ;
the remainder of the abdomen is devoid of scales.

Wings with the veins clothed with black and white scales
forming dark and light areas as follows:— The costa shows four
large dark-scaled areas and two small ones ; the first longitudinal
vein shows dark-scaled areas exactly corresponding to those on the
costa except that the large middle area is divided into three by two
small white spots. The second longitudinal vein has one dark spot
on its main stem and two on each of its branches. The third longi-
tudinal vein is white-scaled except for a small dark area at its be-
ginning and another at its termination. The fourth longitudinal
vein has three small spots on its main stem, and two on each of its
branches. The fifth longitudinal vein has one small dark area on its
main stem, three on its anterior branch, and one on its posterior.
The sixth longitudinal vein shows two dark-scaled areas. The wing
fringe is interrupted by light-scaled areas at the terminations of all
the longitudinal veins and their branches,

90]

Anopheles fuliginosus.

The legs are black ; in the fore and mid legs each tarsal segment,
except the fourth and fifth, has an apical white band ; in the hind
legs the tibia and the first and second tarsal segments have apical
white bands, the third and fourth tarsal segments have both basal
and apical white bands, and the fifth tarsal segment is wholly white.

Habitat. — Karwar (Bombay Presidency) ; Goa.

Time of capture. — Karwar in June (Dr. Cogill) ; Goa in
February (E. H. Aitken).

Observations. — This species differs from A. maculatus (Theo-
bald) in the presence of scales on the last segments of the abdomen,
in the palp mrakings, and in its unspotted legs.

The characters of the head of the larva are shown in the figure.

8. ANOPHELES FULIGINOSUS (Giles).
Coloured PL V. PL V, Fig. 2 ; PL X, Fig. 4.

References .-—Giles, Handbook Mosq., 1st Ed., p. 160 ; Theobald, Monog. CuliciH.,
Vol. I, p. 122 ; Vol. Ill, p. 93 ; Liston, Ind. Med. Gaz.t 1901, p. 441.

Synonym, Nyssorhynchus Fuliginosiis (Theobald).

This is a very dark mosquito with white spots on the wing,
without speckled femora or tibiae, and with the last three segments
of the tarsus of each hind leg white.

The palpi have white tips, and there are white-scaled bands
at the joints between the fourth and third, and third and second,
segments of the palpi. The dark scales on the second segment
are longer than those on the other segments.

The proboscis is black-scaled with a white tip.

The head is covered with black and white scales, the latter
being most numerous on the occiput.

The dorsal surface of the thorax is covered with white scales.
A median and two lateral darker longitudinal lines can be indistinct-
ly made out. The lateral aspects of the thorax are dark.

The abdomen is dark coloured, and covered with numerous
light yellow hairs ; a few dark scales are to be found on the posterior
extremity of the abdomen.

The wing veins are covered with short spindle-shaped scales,
and the wings are for the most part black. The costa has five small
white spots, one of which is situated at the apex of the wing.

[91

Anopheles fuliginosus.

The first longitudinal vein has six white spots. The outer two
correspond to the outer two on the costa. The next two are very
minute, and situated behind the third dark-scaled area counting from
the apex of the wing. The fifth white-scaled portion corresponds to
the fourth on the costa. The sixth white spot is situated behind the
fifth on the costa, but is considerably larger than that costal spot.

The second long vein has a very few white scales at its bifurca-
tion, and a few on its posterior branch.

The third longitudinal has three white-scaled portions, one
small one near its origin, a median long light-scaled portion, and a
terminal small white spot.

The fourth longitudinal has a few white scales at its bifurcation,
and a white-scaled portion on each of its branches.

The fifth longitudinal has two white-scaled areas OH the main
trunk, two white-scaled portions on its anterior branch, and only one
on its posterior branch.

The sixth longitudinal has three white spots. The termina-
tions of all the long veins are white-scaled, and at these points the
wing fringe is interrupted by white scales.

The legs are of a dark brown or black colour. In the fore legs
there are white scales at the distal extremities of the femora, tibiae
and all the tarsal segments except the last two. The middle legs
have corresponding white points to those on the fore legs, but there
is also a characteristic large white spot on the posterior aspect of
each femur near its apex. There are no white scales at the distal
extremities of the three last segments of the tarsus. There are
white scales at the distal extremities of the femur, tibia, first and
second tarsal segments of each hind leg. The last three tarsal
segments are entirely white.

Characters of the larva (PL V, Fig. 2 ). — The median frontal hairs
are slightly branched ; the external frontal hairs are much branched
so as to form a small tuft in front of the whorl organs.

There is no branching hair on the antenna as the larva of

o

barbirostris and nigerrimus. The thorat does not carry a pair of
palmate hairs.

Habitat and observations. — This is a very common and widely
distributed species in India. It occurs in Calcutta and many places
in the plains of Bengal, in Kurseong (at an elevation of 5,000 feet),

92]

Anopheles fuliginostts.

in the Punjab (Lahore, &c.), in Madras, and several places on
the East Coast, in the Central Provinces (Nagpur, &c. ), in Southern
India ( Travancore), in Bombay, in the Berars ( Ellichpur , and in Goa.

In Calcutta it was the commonest species in the Fort, and in
Nagpur it was also found in large numbers in the houses ; in other
places it is rarely found in houses, and approaches in habits to
barbirostris and niyerrimus.

In Nagpur and in Madras its larvse were found in large
natural ponds with grass and weed at the edges ; in the Punjab
its larvae occur along with those of niyerrimus and barbirostris
in shady, weed-grown pools under trees. In Bombay it is fre-
quently found in tanks.

The characters of fuliginosus are sufficiently well marked
to easily distinguish it from other Indian species ; the white patch
near the lower end of the femur in the mid legs is a very constant
and characteristic marking.

Variations. — Major Adie, I.M.S., has noted that the number
of white bands on the palpi and the number of pure white hind
tarsi, as well as the distribution of white scales on the veins of the
wings, are not by any means constant in this species. A common
variety having four white palpal bands and two white hind tarsi is
found in the Punjab throughout the winter. This variety, if
examined alone, might easily be taken for a new species, but breed-
ing experiments have shown that it is not so. An interesting
observation by Major Adie, confirmed by one of us, is that at the
end of the autumn in the Punjab the ordinary form of this mosquito
is gradually replaced by the variety with four white palpal bands
and two white hind tarsi, and that in the spring a return to the
ordinary form occurs — an excellent instance of " seasonal variation "
in mosquitoes.

9. ANOPHELES JAMESI (Theobald).
(Coloured Plate VI.)

References: — Theobald, Monog. Culicid., Vol. I, p. 134; Giles, Handbook
Mosq., 2nd Ed., p. 299, and Rev. of Anoph., p. 43,

Synonym, Nyssorhyiichus Jarnesii (Theobald).

This is rather a small black and white mosquito with three
narrow light bands on its palpi, with speckled femora and tibiae,

[93

Anopheles jamesi.

and with the last three segments of the tarsus in the hind legs
entirely white.

The palpi have three light-scaled bands ; the terminal white
band is broader than the other two, which are situated at the
joints between the second and third, and third and fourth, segments
of the palpi. The proboscis is black, with white scales at its tip.
The head is covered with white and black scales ; the former more
numerous on the occiput, the latter on the nape.

The dorsal aspect of the meso-thorax is covered with white
scales, the lateral surfaces are darker and less covered with hairs
and scales.

Abdomen dark coloured, adorned with hairs and scales, the
latter being, as in A. fuliginosus, most numerous towards the
posterior and lateral surfaces of the abdomen.

The wing veins are covered with black and white scales.

The costa has four distinct white spots, as well as a white-
scaled area at its distal extremity and some white scales on its
proximal portion.

The first long vein has white spots corresponding to those on
the costa, except that the proximal white spot is large and
extends from the base of the wing to the second costal spot.
There are in addition two minute white spots beneath the central
large black-scaled costal area.

The second long vein, mostly white-scaled, has a black-scaled
area on the middle of the main trunk, one black-scaled area on
the anterior branch, and two on the posterior branch.

The third long vein has a few white scales at the points where
the transverse veins join this vein, also a larger white-scaled area
in the middle of its course.

The fourth long vein is mostly white-scaled, but has two dark-
scaled areas on the main stem, and two on each of its branches.

The fifth long vein is mostly white-scaled, with one black spot on
its main stem, and some dark scales at its bifurcation. There are
two dark spots on the anterior and one on the posterior branches.

The sixth long vein has three dark-scaled spots. All the
legs have white-speckled femora, tibiae and first tarsal segments.
There are white scales at all the joints of the legs. The third,
fourth and fifth tarsal segments of the hind legs are entirely white,

941

Anopheles maculipalpis.

Characters of the larva. — Both the median and external
frontal hairs are branched, but not so thickly as in the larva of
maculipalpis.

There is a pair of palmate hairs on each segment of the
abdomen from the first to the seventh and a rudimentary pair
on the thorax. The shape of the leaflets resembles that of the
palmate hairs of maculipalpis.

Habitat and observations. — This mosquito is rare in India,
though several closely allied species have been described under its
name. It occurs in the Central Provinces (Nagpur), in Bombay,
in Southern India (Travancore), and Calcutta. It most nearly
resembles fuliginosus, but is distinguished by having speckled legs.

From maculipalpis it may be distinguished by the characters
of the palp markings, by the presence of white scales at all the
joints of the legs and by having a white tip to its proboscis.

From theobaldi it may be distinguished by its darker wing,
and by having the last three hind tarsal segments pure white
instead of only two as in that species.

10. ANOPHELES MACULIPALPIS (Giles).
Coloured Plate VII, Plate IV, Plate X, Fig. 5.

References : — Giles, Handbook Mosq., 2nd Ed., p, 297, and Rev. Anoph., p. 42 ;
Theobald, Monog. Culicid., Vol. Ill, p. 96.

Synonym, Nyssorhynchm Maculipalpis (Theobald).

This is a beautiful black and white mosquito very much like
A. fuliginosus, but with lighter wing and speckled legs. It has, in
addition, white scales on the dorsal surface of the third segment
of the palpi.

The palpi have three distinct white bands, and in addition a
few scattered white scales on their third segments. The two
anterior light bands are broader than the posterior band. The
proboscis is black including the tip, but there are a few light
scales at the labellar joints. The head is covered with white and
black scales, the former predominating on the occiput, the latter
on the nape.

The dorsal surface of the thorax is covered with white
scales and hairs ; the lateral surfaces of the mesothorax are darker
and mainly adorned with dark hairs.

[95

Anopheles maculipalpis.

The abdomen is of a dark colour and thickly covered with
light and dark hairs. As in fuliginosus and jamesi, scales are
present only on the last one or two segments of the abdomen.

The wings are covered with black and white scales, the
former being most numerous.

The costa has three distinct white spots, and in addition the
distal extremity is white, and there are two minute white spots on
the proximal portion.

The first long vein has three white spots corresponding to
the three prominent ones on the costa. Its distal and proximal
extremities are also white-scaled. In addition there are two
white spots beneath the largest central black-scaled area on
the costa.

The second long vein has white scales at the points where the
transverse veins meet it, and at its bifurcation, and one spot on
each of its branches.

The third long vein is white -scaled at the position of the
transverse veins, and it has two other white-scaled portions between
that point and its termination, which is also white-scaled.

The fourth long vein is for the most part dark-scaled, except
at its proximal extremity, at the position of the transverse veins,
at its bifurcation, and at a spot on each of its branches.

The fifth long vein is for the most part light-scaled. It has
two dark spots on its main trunk, three on its anterior branch, and
two on its posterior branch.

The sixth long vein is for the most part light-scaled, but has
three dark-scaled spots.

The wing fringe has light scales at the distal extremity of ail
the long veins.

The femora, tibiae, and first tarsal segments of all the legs are
speckled with white spots, and the joints between these segments
have white scales. There are light scales at the joints between
the tarsal segments, except between the fourth and fifth segments
in the fore and mid legs, and between the first and second segments
in the hind legs. The three terminal segments of the hind legs are
entirely white.

Characters of the larva (PI. IV). — The median and external
frontal hairs are thickly branched, the branches of the external

96]

Anopheles theobaldi.

rental hairs being arranged like the veins of a leaf. A prominent
pair of palmate hairs is present on the thorax in addition to those
on the abdominal segments. The shape of the palmate hair leaflets
is shown in the figure (B).

Habitat and observations. — This species occurs in small num-
bers in the Central Provinces (Nagpur), and more commonly in
some parts of the South of India, Travancore, Goa, &c., and in the
Bombay Presidency (Karwar). Outside India it occurs in
Mashonaland and Mauritius. A variety in which the hind legs are
less banded is described by Mr. Theobald under the term indiensis.

11. ANOPHELES THEOBALDI (Giles).
(Coloured Plate VIII.)

References : — Giles, Handbook Mosq., 2nd Ed., p. 299, and Rev. of Anoph., p. 43 ;
Listen, Ind. Med. Gaz., Dec. 1901 ; Theobald, Monog. Culicid., Vol. Ill, p. 95.

Synonym, Nyssorhynchus Theobaldi (Theobald).

Palpi with three white bands, the two anterior of which are
broad and the posterior narrow. Wings light coloured, spotted with
black. Legs speckled ; the last two segments of the tarsi of the
hind legs pure white.

Palpi black with three white bands ; the apex is white-scaled,
the second band is at the joint between the apical and the third
segment, and the third band is at the joint between the third and
second segments.

Proboscis black with a white tip.

Head covered with black and white scales ; a prominent bifid
tuft of white hairs projects forward from the head.

The thorax is covered on its dorsal surface with white scales
and hairs inserted on a dark ground, the scales and hairs being
arranged so as to show a median and two lateral darker lines. The
lateral aspects of the thorax are of a dark colour.

The abdomen is intensely black. It is covered with long white
hairs. Mr. Theobald says that the apical segments have " small flat
scales of a dull golden hue." We have been unable to detect the
presence of these scales in the examination of a number of speci-
mens, and Colonel Giles originally described the abdomen as " nude."
The point is of importance, as the position of the mosquito in the

[97

Anopheles theobaldi.

genus Nyssorhynchus apparently depends upon the presence or
absence of these few scales.

The wings are covered with spindle-shaped scales. The costa
has six black-scaled areas. The black-scaled portion on the centre
of the costa is the largest. Two very small dark spots are situated
at the inner end of the wing.

The first longitudinal vein has four dark markings correspond-
ing with the four outer large dark areas on the costa. The third
dark area from the outer end is almost always divided into three by
the interposition of two small white-scaled spots.

The second longitudinal is for the most part white, but shows
two black- scaled areas on the main trunk and two dark spots on
each of its branches.

The third longitudinal vein is white except for three dark
spots.

The fourth long vein has two long black spots on the main
trunk and two small black spots on each of its branches.

The fifth longitudinal has only one dark spot on the main
trunk, three on its anterior branch, and one on its posterior branch.

The sixth long vein has three dark spots.

The distal extremity of all the veins is light-scaled, and at
these points the wing fringe is interrupted by light scales.

The legs are much adorned with white scales and differ in
detail in the anterior, mid and hind legs. The femora and tibiae of
all the legs are covered with dark and light-scaled spots. The first
tarsal segments too have some white spots. The distal extremities
of the second and third tarsal segments in the fore and hind legs
are white, but black at these points in the middle legs. The fourth
and fifth segments in the hind legs are entirely white, while they are
entirely black in the other legs.

Characters of the larva. — The frontal hairs are slightly branch-
ed or frayed, There are palmate hairs on the abdominal segments
and a rudimentary pair on the thorax. The shape of each leaflet
is characteristic, and the terminal filaments are very short and
blunt.

The larva of this species differs from most of the others in
this group in that it is more frequently found in streams than in
still water.

98]

Anopheles maculatus.

Habitat and observations. — The Berars (Ellichpur); the
Central Provinces (Nagpur) ; the Jeypore State ; Behar, Bombay.

The separation of this mosquito, as a distinct species, depends
chiefly on the characters of the larva, for except in colour markings
there are few or no structural characters in the adult by which it
can be separated from allied species.

For purposes of identification, however, the fact that only
the last two hind tarsal segments are pure white will serve to dis-
tinguish it from other species.

It has been proved that, under experimental conditions,
human malaria parasites can develop in this mosquito.

12. A.NOPHKLKS MACULATUS (Theobald).

References: — Theobald, Monog. Culicid., Vol. I, p. 171 ; Vol. Ill, p. 96.
Synonym, Nyssorhynchus Maculatus (Theobald).

Palpi with three white bands. Thorax covered with white-
scales ; abdomen black, with many hairs but no scales. Legs
speckled ; last tarsal segment of the hind legs pure white. Wings
spotted.

Head black, with white upright scales in front and black
ones behind ; a prominent tuft of white hairs projects forwards from
the head.

Palpi with dark scales, and three white bands, the outermost
band includes the tip and is separated by only a few black scales
from the next which is equal to it in breadth ; the third band
is narrow ; proboscis brown with a white tip ; antennae brown
with white hairs.

Thorax covered with white spindle-shaped scales and some
golden hairs ; scutellum with white scales and long bristles.

Abdomen dark brown with many golden brown hairs, but no
scales except on the abdominal processes.

Legs with the femora, tibiae and first tarsal segments speckled
with white scales ; in the fore and mid legs the tarsal segments
except the fourth and fifth have apical white bands ; in the hind
legs the first tarsal segment (metatarsus) is brilliantly spotted with
white spots and has an apical white band, the second tarsal segment
is unspotted and has a broad apical band, the third has broad basal

[99

Anopheles maculatus.

and apical bands, the fourth has also broad basal and apical bands,
and the fifth is pure white throughout its length.

Wings with the veins clothed mostly with pale narrow scales
and with some black ones, forming spots arranged almost exactly
as in the wings of theobaldi.

Characters of the larva. — The frontal hairs are simple and un-
branched. Palmate hairs are borne by the second to the seventh abdo-
minal segments ; the terminal filament of each leaflet is very short.

Habitat and observations. — This species occurs in Lahore in
March and April ; in the Bengal Duars (August and September),
and at Kurseong at an elevation of 5^000 feet. It also occurs in
Hong- Kong (China) and in the Straits Settlements.

This "anopheles " very closely resembles theobaldi and is pro-
bably only a geographical variety. The difference in the frontal hairs
of the larva is noteworthy, but such minor differences have been
noted in larvae of undoubtedly the same species. As in theobaldi
we have been unable to detect any scales on the abdomen (excluding
the abdominal processes) of this species, and for this reason we
should be inclined to remove it, with theobaldi, from the genus
Nyssorliynchus, in spite of the fact that Mr. Theobald regards it
as the type-species of that genus At any rate, if scale structure
is of any generic value, it seems wrong to place this species in the
same genus as stephensi and willmori, the abdomens of which are
almost entirely covered with large scales.

The different mosquitos in this group are very liable to be
mistaken for one another. They can readily be divided into two
groups according as the tibiae and femora are (a) unspotted, (b)
spotted.

Under (a) would come karwari and fuliginosus. As a rule,
karwari has four bands on the palpi while fuliginosus has only
three, but in this latter mosquito there are occasionally four bands
on the palpi. Again, karwari has, as a rule, only one segment
entirely white in the hind tarsus, while fuliginosus has three, but
occasionally only two. These mosquitos, however, are most easily
distinguished from one another by the fact that the wing of karwari
is very much lighter than that of fuliginosus.

Under (b) come jamesi, macuiipalpis, theobaldi, and maculatus.
The two former can be separated by the fact that they have

100"!

Anopheles nagpori.

at least three hind tarsal segments entirely white, while the others
have less than three.

Jamesi is most readily distinguished from maculipalpis by an
examination of the palpi, the former has a broad terminal and two
narrow white bands without additional speckling, while the latter
has two broad distal and one narrow basal band and has additional
speckling.

Theobaldi is distinguished from maculatus only by the fact that
the former has two segments in the hind tarsus wholly white, while
the latter has only one.

We may here refer to a specimen which Mr. Theobald (Mono-
graph, Vol. Ill, p. 96) thinks probably represents a distinct species,
and which for the purposes of our synoptic table (page 32) we have
named A. nagpori. It was found by Dr. Stephens at Nagpur
(Central Provinces). Its main characteristics are as follow:~(l ) The
palpi are marked with three narrow white bands, the terminal of
which is some distance below the tip so that the tips of the palpi
are black. The base of each palp is densely black-scaled. (2) In
the fore leg there are no white bands at the apices of the femur
and tibia, but there is a small white band at the apex of each tarsal
segment. In the middle leg there are no white bands at any
joints. In the hind leg there is a faint white spot at the apex of
the tibia, and a white spot at the apices of the first and second
tarsal segments. The fourth and fifth and two-thirds of the
third tarsal segments of the hind leg are pure white. (3) There
is no speckling of the legs or palpi.

GROUP V.

Types : — A . jeyporiensis, A. listoni, and A. culicifacies.

13. ANOPHELES JEYPORIENSIS (James).
(Coloured Plate IX, Plate VII, Fig. 2.)

References : — James, " Malaria in India," p. 32 • Theobald, Monog. Culicid.,

Vol. Ill, p. 66.

Synonym, Pyretophorm Jeyporiensis (Theobald).

A. small dark mosquito. Palpi with three white bands.
Thorax with many narrow curved creamy scales in the middle, dark
brown at the sides. Abdomen black with many golden hairs, but

[101

Anopheles jeyporiensis.

no scales. Legs black, but with minute white bands at the tarsal
joints formed by white scales on the apices of the segments.

Palpi black, covered with scales and with three light-scaled
bands ; the terminal band, which includes the tip, is broader than
the other two, which are situated at the joints between the third
and fourth, and second and third segments.
Proboscis dark brown with a paler tip.

Head black with white upright-forked scales in front, black
ones behind ; a dense tuft of white hairs projects forwards from the
head ; antennae brown with silvery hairs.

Thorax dark with a patch of long narrow curved white scales
on the dorsum and black hairs forming longitudinal lines.

Scutellum black with dark border bristles ; abdomen blackish
brown, thickly covered with fine golden brown hairs, but with no
scales.

The wing veins are covered with long spindle-shaped scales.
The costa is dark brown in colour, and interrupted by five minute
yellowish white areas ; in addition the distal extremity of the costa
is white. The proximal white-scaled interruption is very minute.

The first long vein has four white-scaled portions, correspond-
ing to the four distal white-scaled areas of the costa. In addition
there is a large white-scaled portion extending from the base of the
wing to the second most internal costal white spot.

The second long vein has a few white scales at the points
where the transverse veins join it. There are a few white scales at
the point of bifurcation, and at the distal extremity of each branch
of this vein. There is, in addition, a white-scaled portion in the
middle of the anterior branch.

The third long vein is mostly white, except for a small portion
just beyond its origin.

The fourth long vein is white-scaled at its proximal extremity ;
it is dark-scaled for the rest of its course, except where the transverse
vein joins it. There are also two white-scaled areas on each of the
branches ; the distal extremities of the branches are white-scaled.

The fifth long vein is chiefly white-scaled. There is one black-
scaled area on the middle of the main trunk. This vein is also
dark-scaled at its bifurcation. There are two dark-scaled spots on
the anterior branch and one on the posterior branch.

IO2]

FJG. 1.

PLATE VIL

FIG. 2.

A.

PLATS VII. Fig. 1 —The larva of ^. littoni. A.— General view ; JS.- Fruiital hairs umgnitied ;
/"it/. 2. -The larva of A. jfi/iwriemifs. In figure B the " posterior hair" of the rixhf

r.— A palmate hair
ide i* seen.

Anopheles listoni.

The sixth long vein is covered with white scales, except for a
few dark scales about the middle of its course and a few near its
termination.

The wing fringe has light-scaled areas opposite the extremities of
each long vein.

Legs quite black but with minute white bands at each joint
formed by white scales on the apices of the segments.

Characters of the larva (PL VII, Fig. 2). — Both the median
and external frontal hairs are thickly branched, this character en-
abling jeyporiensis to be at once separated as a species distinct
from listoni and culiciafcies, the larvaj of which have simple
frontal hairs. The thorax carries a prominent pair of palmate
hairs in addition to those on the abdominal segments.

Habitat and observations. —This new species was first found in
the Jeypore State by Drs. Stephens and Christophers. It also
occurs in the Central Provinces (Nagpur), and a specimen has lately
been sent by Mr. Aitken from Jakot (Southern India). It has fre-
quently been found in Bombay. In all these places it was found
breeding either in streams or in the flowing water of rice-fields. It
is evidently closely allied to listoni and culicifacies. From the
former the adults can be distinguished by the differences in the wing
markings and by the presence of light scales at all the joints of the
legs ; from the latter by the differences in the wing markings.
According to Mr. Theobald the meso-thoracic scales are " narrow
curved" in jeyporiensis and "hair-like" in culicifacies, but these
differences are not easy to make out.

14. ANOPHELES LISTONI (Listen).
(Coloured Plate X, Plate VII, Fig. 1.)

References :— Listen, Ind. Med. Gaz., Dec. 1901 ; Theobald, Proc. Roy. Soc.,
Vol. LXIX, p. 378, and Monog. Culicid., Vol. Ill, p. 27 ; James, " Malaria in India,"
p. 31 ; Giles, Rev. of Anoph., p. 28.

Synonyms , Myzwnyia Listoni (Theobald).

A. fluviatilit (James).
A. ckristophersi (Theobald).

This is a very dark, small mosquito, readily distinguished by
its entirely black legs and white third longitudinal vein. The palpi
have three almost equal white-scaled bands, one at the apex,

[103

Aitopheles listoni.

another at the junction between the fourth and third, and a third at
the joint between the third and second segments.

The proboscis is brown with a yellowish- white tip. The head
is covered with the usual dark brown and white upright scales, and
there is a frontal tuft of hairs

The thorax is covered with white hair-like scales, and yellowish
hairs, inserted on a dark black background.

The scales and hairs are so arranged as to show a median, and
two less distinct, lateral, longitudinal darker lines. The lateral
aspects of the meso-thorax are of a black colour.

The abdomen is of a dark black colour and is covered with
numerous long yellowish-white hairs.

The wings are covered with long spindle-shaped scales.

The costa has four yellowish-white areas. The smallest of
these is situated at the apex of the wing ; the others increase in
size from this point inwards.

The first long vein has four light-scaled areas corresponding
with the four light-scaled areas of the costa, but in addition there
is a larger white-scaled portion at its inner extremity.

The second long vein shows three small white-scaled areas, the
outermost is situated at the bifurcation of the vein and in part in-
volves both branches. The other two are situated at the position
of the transverse veins.

The third long vein, in contrast to the other veins, is for the
most part light-scaled, but has two small dark-scaled areas towards
its inner extremity, and one dark-scaled portion at its outer end.

The fourth long vein is for the most part dark-scaled, except
for a short distance at its inner extremity, where it is light-scaled,
and for a few light scales at the transverse veins, and at its bifur-
cation.

The fifth long vein is white for most of its inner portion, ex-
cept for a small dark-scaled spot towards its inner end. This vein is
black-scaled at its division into branches. The anterior branch is
dark throughout, except for a few light scales at the transverse vein
and at its outer extremity. The posterior branch has a short white-
scaled portion shortly after it leaves the parent trunk, and has a
few light scales at its distal end. The remainder of this branch is
dark-scaled.
104]

Anopheles listoni.

The sixth long vein is for the most part black-scaled, but shows
two small white areas, the one at its inner extremity, and the other
between the two black-scaled portions. The distal extremities of
all the long veins, except the sixth, are white-scaled, and at these
points the wing fringe is interrupted by light scales.

The legs are dark-scaled throughout.

Variations. — The following are the most common variations —

(1) the long dark basal costal spot is occasionally interrupted
by a few light scales about its middle ;

(2) the length of the white-scaled area on the third long vein
may be considerably diminished by the encroachment of black scales
from either end of the vein ; indeed this vein is occasionally found
black throughout ;

(3) a light-scaled interruption occasionally occurs on the middle
of the anterior branch of the fifth long vein ;

(4) light scales may occasionally be found at the distal extremity
of the tibiae, and there may sometimes be a tendency to formation of
light bands at the tarsal joints.

Characters of the larva (PI. VII, Fig. 1). — The frontal hairs
are simple and unbranched. In addition to the palmate hairs on the
abdominal segments there is a well-developed pair on the thorax.
The terminal filament of each leaflet is short.

The characteristic pattern on the dorsum of the head of the
larva is shown in the figure.

Habitat and observations. — This species occurs in the Berars
(Ellichpur), in the Central Provinces (Nagpur), in the Bengal
Duars, in the Jeypore State, in Goa, Bombay, and the Hyderabad
State (Aurungabad).

It is apparently absent from the Punjab.

Its larvae are usually to be found in clear streamlets with grassy
edges. It has been shown to be the carrier of malaria in the Duars ;
experimentally also it has been proved that the parasites of human
malaria readily develop in it.

In the adult stage this species closely resembles jeyporiensis,
but it may be distinguished by the differences in wing markings and
by the fact that, as a rule, the legs have no white scales at the joints.

Considerable confusion has arisen regarding the correct specific
name of this species, and it seems necessary to give the following

[105

Anopheles culicifacies.

brief history of its discovery. It was first found by Captain Liston
who sent it with specimens of culicifacies to Colonel Giles, at the same
time pointing out the differences between the two species. Colonel
Giles proposed to name it listoni, and it was therefore described
under this title by Captain Liston (Ind. Med. Gaz., Dec., 1901). In
the meantime the labels on Colonel Giles' specimens were apparently
lost, and when his description appeared it was evident that under
the title listoni, he had only redescribed a specimen of culicifacies.
Thus listoni (Giles) is merely a variety of culicifacies (see
Rev. Anoph., p. 30). In 1902 the same mosquito was found
in the Duars by the Royal Society's Malaria Commissioners.
At first they considered that it was identical with the African
species funestus (Giles), but as this view was not shared by
Mr. Theobald, the mosquito was described by Captain James
under the title fluviatilis (" Malaria in India," p. 31). The
specimens sent to Mr. Theobald were described by him about the
same time under the title Christopher si. Subsequently we were able
to point out to Mr. Theobald that the species was identical with
that originally described by Captain Liston under the title listoni,
and the latter name must therefore be regarded as correct. Our
illustrations were prepared before the correct nomenclature of this
species had been worked out, and in the coloured plate it appears
under the title fluvintilis. We have already pointed out, however,
that there is no good reason for regarding this species as distinct
from funestus (Giles), and it is very probable that all the other
names will soon be sunk under the latter title.

15. ANOPHELES CULICIFACIES (Giles).
(Coloured^Plate XI. Plate IX, Fig. 2 ; Plate VIII, Fig. 1.)

References: — Giles, Ento. Mo. Mag., 1901, p. 197; Handbook Mosq., 2nd Ed.,
p. 317, and Rev. of Anoph., p. 29 ; Theobald, Monog. Culicid., Vol. Ill, p. 39 ; Lis-
ton, Ind. Med. Gaz., Dec., 1901.

Synonym, Myzomyia Culicifacies (Theobald).

This is a small dark mosquito closely resembling listoni, but
distinguished from that mosquito by having the third longitudinal
vein dark-scaled, and by the presence of a few light scales at the
tibio-metatarsal joints.

106]

Anopheles culicifacies.

The palpi have three small, almost equal, yellow areas, namely,
at the apex, at the joint between the third and fourth segments,
and at the joint between the third and second segments.

The head is covered with yellowish-white and brown upright
scales, and has a small frontal tuft of white hairs.

The thorax is covered with brown and yellow hairs and hair-
like scales inserted on a dark back-ground. There is a distinct
median, dark, longitudinal line. The lateral aspects of the thorax
are darker than the dorsum.

The abdomen is of a dark brown colour and is covered with
long yellow hairs but is without scales.

The wing is covered with narrow spindle-shaped scales.

The costa has five yellowish -white scaled portions, the innermost
of which is of very small size ; the outermost is apical in situation.

The first longitudinal vein shows five small yellow-scaled areas
corresponding exactly with the similar costal areas.

The second long vein has three light-scaled portions, the two
inner are situated at the transverse veins, while the outer is situ-
ated at the bifurcation of the vein, and involves, for a short
distance, both branches.

The third long vein is dark-scaled throughout, except at its origin.

The fourth long vein has three light-scaled areas, one towards
its inner end, one at the situation of the transverse veins, and one
at the point of bifurcation ; the light-scales are continued on the
branches for a short distance.

The fifth long vein has only one light scaled area on the main
stem, and one on each of its branches.

The sixth long vein has one light-scaled spot. The distal ex-
tremities of the posterior branch of the fourth longitudinal, and the
anterior branch of the fifth longitudinal are alone light-scaled, and only
at these points is the costal fringe interrupted by lighter scales. *

The legs are of a dark brown colour throughout, but some-
times show, at the distal extremity of the tibia, a small spot of
yellowish scales.

Variations. — There may be (1) an increase in the number of
light-scaled interruptions in the wing fringe; (2) a tendency to

* These two light-scaled areas on the wing fringe are sometimes indistinct. This is shown
in the wing of the right side in the specimen from which the coloured plate was drawn.

[107

Anopheles culicifacies.

banding at the tarsal joints ; (3) variations in the relative positions
of the transverse veins.

Characters of the larva (PI. VIII, Fig. 1). — Both the median
and external frontal hairs are simple and unbranched. There is a
pair of palmate hairs on the thorax as well as those on the abdomi-
nal segments, but the thoracic pair are not as well developed as in
the larvas of listoni or jeyporiensis, and the terminal filament of
each leaflet is longer than in either of those larvae. The pigment
dots on the dorsum of the head are arranged in a characteristic
manner.

Habitat and observations. This species is widely distributed
in India. It occurs in the Punjab (Lahore, Mian Mir, Ferozepore,
&c.), in Madras, and several places on the East Coast (Ennur, Ar-
magaon, &c.), in the Central Provinces (Nagpur), in the Jeypore
State, in the Berars (Ellichpur), in Goa, in Bombay, and in the
Hyderabad State (Secunderabad and Aurungabad).

In the Punjab its larvae can be found in the irrigation water-
courses throughout the year, but adults cannot be detected in
houses during the cold months from December to March. It is
commonly found in drying up river beds in the Deccan, and is found
in houses there throughout the hot and cold weather.

In the south of India it has been found breeding in rice-fields
(Aitken), in " borrow pits" by the side of railways, and in pools in
the beds of rivers.

The adults are peculiar in that they do not adopt the charac-
teristic attitude of other " anopheles" when resting on a wall or roof,
but sit more or less like a "culex" with the body parallel to the wall.

This species has been proved to be a very efficient malaria-car-
rier in Mian Mir (Punjab) and in Ennur (Madras). Experimen-
tally also it has been shown that the parasites of the three varieties
of malarial fever can readily develop in it.

A. culicifacies can be distinguished from listoni and jeyporiensis
by the fact that it has the third longitudinal vein entirely black-
scaled, and by having only two white interruptions on the wing
fringe instead of several as in those species.

A peculiarity of this species is the fact that the relative posi-
tions of the transverse veins of the wing to one another vary con-
siderably. (See James, " Malaria in India," p. 29.)

108]

FIG. 1.

PLATE VIII

FIG. 2.

i

LATE VIIli Fig. 1. — The larva of A. culicifacies. Fig. &.— The larva of A. turkhttd,i. Fig. B shows the long " posterior hair " of the right side.

Anopheles rossi.

Colonel Giles, in the 2nd Edition of his Handbook, describes
the abdomen as being completely clothed with yellowish and deep
brown scales. This is incorrect, for the abdomen is devoid of scales.
The male genitalia are also wrongly described as being characteristic.
These points are corrected in his "Revision of the Anophelinae."

Mr. Theobald now admits that his indica is nothing more
than a specimen of culicifacies.

GROUP VI.

Types : — A. rossi and J. stephensi.

16. ANOPHELES ROSSI (Giles).
(Coloured Plate XII. Plate VI, Fig. 1 ; Plate X, Fig. 3.)

References: — Giles, Handbook Mosq., 1st Ed., p. 149; Theobald, Monog. Culicid.,

Vol. I, p. 154, and Yol. Ill, p. 45.

Synonym, Myzomyia Rossii (Theobald).

A light brown mosquito. Thorax with scattered whitish
scales, especially anteriorly and at the sides, and many hairs ; abdomen
with numerous yellow hairs ; palpi with three white bands : legs
not speckled but with tarsal bands ; wings spotted.

Head covered with black and white scales and with a well-
developed frontal tuft of white hairs projecting forwards. Palpi
with three white bands, the outermost of which includes the tips
of the palpi and is broad ; the other two bands are narrow ; the
first is situated at the junction of the fourth and third segments,
and the other at the junction of the third and second segments of
the palp.

Proboscis brown with a yellow tip ; antennae brown with pale
hairs. Thorax furnished with golden hairs and narrow hair-like
scales, the latter predominate anteriorly and laterally ; the scales
and hairs are so arranged that three somewhat indistinct longi-
tudinal lines can be made out, the most conspicuous being the
central one.

The abdomen is densely covered with yellowish brown hairs.

The scales on the wings are spindle-shaped.

The costa has seven black-scaled areas. The black spot on the
middle of the costa is the largest. Three of the black spots at the

[109

A nopheles^rossi.

inner end of the costa are very small, and may be more or less
united together.

The first long vein shows five dark spots : the outer four of
these have a similar situation to the outer four on the costa ; the
fifth lies close to the inner end of the vein. .

The second long vein has two dark spots before its bifurcation.
There are, as a rule, two black-scaled spots on each of the two
branches into which this vein divides.

The third long vein has three dark spots, all small in size.

The fourth long vein has two dark -scaled portions before its
bifurcation, and on each of its branches there are two dark spots.

The fifth long vein, before it bifurcates, has one dark spot ;
its anterior branch has three dark spots, while the posterior has
only one.

The sixth long vein has two dark spots —one near the middle,
the other near the termination of the vein.

The distal extremity of all the wing veins is light-scaled and
at these points the wing fringe is interrupted by light scales.

The legs are of a brownish hue and show lighter scaled spots
of a yellowish colour at the distal extremities of the femur, tibia,
and all the tarsal segments except the last. The marks on the
tarsi are at the joints between the segments. The marks on the
tarsal joints of the hind legs are smaller than those on the other legs.

The chief variations to be found in this mosquito are :

1. Variations in the number of costal spots. This is brought
about by the union of one or more of the normal costal spots,
especially those situated near the base of the wing. Other minor
differences are to be found in the number and arrangement of the
dark areas in other parts of the wing field.

2. There is occasionally a tendency to mottling on the femur
and tibia, but this is always indistinct as compared with stephensi.

3. The markings on the tarsi may be more distinct in some
specimens than in others.

4. Like many other " anopheles " the relative position of the
transverse veins to one another is variable.

Characters of the eggs and larva (PL VI, Fig. 1). — The eggs
of this species are characterised by having a very broad deck
surface and by the presence of a broad fringe passing all round the

no]

PLATE IX.

PLATE IX. Wing scales of "A nop/teles."

1. A. ntuoi.latHS. 2. A. culicifacies. 3. A. aitkeni. 4. A. leucopki/rtts variety elei/ans. 5. A. listoni.
6. ^-1. pvlclierrimus.

Anopheles rossi.

edge of this surface (p. 39, fig. 8, 3). Both the external and median
frontal hairs of the larva are simple and unbranched. Palmate hairs
are present from the second to the seventh abdominal segments ;
the terminal filament of each leaflet of the palmate hairs is very
long. The pattern on the dorsal surface of the head of the larva
is characteristic and fairly constant.

Habitat and observations. — A. rossi is common throughout
India, and has been found at elevations above 5,000 feet. Its
favourite breeding place is usually a muddy pool or shallow tank
among native huts, and after the rains both larvae and adults may
be present in enormous numbers. In the Punjab (Lahore, Mian
Mir), it is rare before the commencement of the rains, owing pro-
bably to the absence of suitable breeding places, for it does not
usually breed in the irrigation watercourses as A. culicifacies does.
In September, October and November, however, enormous numbers
can be caught in the native huts. The larvae of this species have
occasionally been found in very foul water, and at Ennur near
Madras, its larvae were found in water containing 2*8 per cent, of salt.

In the Deccan, in Bombay, and in Calcutta the larvae are found
in tanks during the dry weather. During the rains they disappear
from the tanks and are found in large numbers in the small shallow
muddy pools which are then so common by the roadside and in the
open fields.

In the south of India, where suitable breeding places are
present all the year round, A. rossi has no special seasonal preva-
lence and is common throughout the year. In the Madras Presi-
dency it breeds largely in irrigated rice-fields.

A.dult insects of this species are very commonly found in India
in railway carriages, as well as in almost every kind of road con-
veyance, and this is possibly one of the ways by which the species
has become so widely distributed throughout the country.

Outside India it occurs in Penang, the Malay States and
Sumatra.

It has been shown that under experimental conditions the
parasites of human malaria are capable of developing in this species,
but, although so prevalent throughout India, it has never yet been
found infected in nature. In the south of India it is one of the
carriers of Filariasis,

[in

Anopheles rossi.

Characters distinguishing this mosquito from other species. —
From A. stephensi it is distinguished by the absence of scales on the
abdomen, by the markings on the palpi, and by the absence of
speckling of the legs.

This mosquito might be confounded with those of Group II,
especially with punctulatus, but an examination of the palpi would
prevent any error, for the members of that group have four bands
on the palpi.

This mosquito very closely resembles costalis but differs
from it chiefly in the fact that costalis has a white interruption in
the black area on the first longitudinal vein, opposite the penulti-
mate black costal spot, and has three black spots on the sixth longi-
tudinal vein in place of two. These, however, are merely colour
variations and can hardly be considered of specific value.

We can confirm Colonel Giles' statement that there is a tuft of
white scales on the front of the thorax as well as a small patch of
spindle-shaped scales on the last abdominal segment. Mr. Theobald
apparently considers that these scales are absent, and for that reason
has placed the species in the genus Myzomyia. A classification based
upon characters about which it is possible for so much difference of
opinion to exist, cannot, we think, be considered a very useful one.

We may here refer to a specimen which Mr. Theobald has
placed as the type of a new genus Aldrichia. This genus is based
on a single specimen, which was found among the types of A. rossi
deposited in the British Museum. It differs from all other " ano-
pheles " in the fact that the entire dorsum of the abdomen is cover-
ed with flat imbricated scales arranged exactly as in mosquitoes of
the genus Culex. In other respects the specimen, which has been
named Aldrichia error, appears to resemble rossi very closely,
and Colonel Giles is of opinion that in all probability it represents
merely an abnormality. He states that when examining a number
of specimens of culicifacies he came across one the abdomen of
which was similarly scaled (see his description cf this species, Hand-
book, 2nd Ed., p. 317, and his Revision of the Anophelinas, pp.
9 and 29), so that observers should certainly be on the look out for
specimens presenting this curious character, in order that the
question as to whether such specimens are abnormalities or not
may be cleared up.

U2]

X

V

3. J.TCM. i.

C. J.

Anopheles stephensi.

17. ANOPHELES STEPHENSI (Listen).
(Coloured Plate XIII. Plate VI, Fig. 2, Plate X, Fig. 6.)

References : — Listen, Ind. Med. Gaz., December, 1901 ; Theobald, Monog. Culicid.,

Vol. Ill, p. 93.

Synonyms, Nyssorhynchus Stephensi (Theobald).
A. metaboles (Theobald).

Palpi with three white bands and some speckling ; thorax
covered with white scales ; abdomen with many scales and hairs ;
legs speckled but with none of the hind tarsal segments white in
their whole length ; wings spotted.

Head covered with brown and white upright-forked scales ; a
prominent frontal tuft of white hairs projects forwards ; palpi with
three white bands ; the two outer equal and broad, the third narrow ;
tips of the palpi white ; on the dorsal aspect of the third segment
of each palp there are in addition one or two white-scaled spots.

Proboscis brown-scaled with a yellowish tip ; antennas dark-
brown.

Thorax covered on its dorsum with white scales and showing
an indistinct median and two lateral longitudinal dark lines ; lateral
aspects of the thorax dark.

Scutellum with white scales and dark bristles.

Abdomen brown, covered with numerous hairs and scales.

Wing veins clothed with rather broad spindle-shaped scales.

The costa shows six black-scaled areas ; the base of the costa
has dark scales, while the apex has white scales.

The first long vein has four dark-scaled areas corresponding to
the four outer dark-scaled areas on the costa, but the third dark-
scaled area from the apex is divided into two by a narrow white-
scaled interruption, and is shorter than the corresponding costal mark.

The second long vein has a single black-scaled area on the
main stem, and one on each of its branches ; the point of bifur-
cation is white-scaled.

The third longf vein shows two small dark-scaled dots, one

o

near its origin, and the other near its termination.

The fourth long vein shows two dark-scaled areas on the main
trunk, two on the anterior branch, and one on the posterior branch.

The fifth long vein has a single dark-scaled spot on the trunk,
three on the anterior branch, and one on the posterior.

Anopheles Stephens 7.

The sixth long vein has sometimes three, and occasionally
only two dark-scaled spots.

The costal fringe is interrupted by light scales at the outer
extremity of all the longitudinal veins.

The femora and tibiae of all the legs are speckled with white
scales. The distal extremities of the femora and tibiae are covered
with yellowish white scales. The distal ends of the tarsal segments
of the middle and hind legs have yellowish white-scaled bands,
except those of the terminal segments. In the anterior legs, the
second and third tarsal segments have distal yellowish-white bands,
and the first tarsal segment has two additional yellow-white bands.
The fourth and fifth segments are wholly covered with brown
scales.

Characters of the larva. — (Plate VI, Fig. 2). — The frontal
hairs are simple and unbranched. The palmate hairs are borne by
the first to the seventh abdominal segments ; the filaments of the
leaflets are shorter than those of rossi, and this character and the
complete absence of any head pattern serve to distinguish the larva
of this species from that of A. rossi.

Habitat and observations. — This species occurs in the Punjab
(Lahore, Mian Mir, &c.), in Calcutta, in Madras, in the Central
Provinces (Nagpur), and at Ellichpur in the Berars. In Calcutta
the adults were found in native huts along with A. rossi ; in
Madras, it was also found in native houses, and here it was breed-
ing almost entirely in disused wells. In Mian Mir its breeding
places were found to be the tins and vessels of water which are kept
in the lines of native troops in case of fire. This species has not
been found in Bombay, but is very common in Karachi.

It has been proved that under experimental conditions the
parasites of human malaria are capable of developing in this
species.

A. stephenn is in many respects related to pulcherrimus and
willmori, but the wing and thoracic scales are not so broad and there
are fewer scales on the abdomen and more hairs. It can be readily

distinguished from them by the absence of white tarsal segments
on the hind legs.

Mr. Theobald has classed this species in his genus Nyssorhyn-
chus, but an examination of the thoracic scales, on which he lays

114]

Anopheles tiirkhudi.

so much stress, will readily show that these scales differ in shape
from those of most of the other species which he has placed in this
genus, and approximate much more closely to those of willmori
and pulcherrimus. The abdomen of stephensi is also much more
heavily scaled than that of other species classed in the genus
Nyssorhynchus, and it seems to us not improbable that Mr. Theobald
has confused some specimens of this species with specimens of
maculatus. This is certainly the case in the Royal Society's
Reports (sixth series, page 11) in which the descriptions of the
habits and of the larva of the so-called A. metaboles (= stephensi)
should be read as referring to maculatus and not to metaboles
at all. In the same way his figure and description of the larval
palmate hairs of stephensi (Vol. Ill, pages 47 and 85), are incorrect,
and should be read as referring to macuiatus. The terminal
filaments of the palmate hair leaflets of the larva of stephensi are
long and pointed as in Plate VI, Fig. 2.

GROUP VII.

Type : — A. turkhudi.
18. ANOPHELES TURKHUDI (Listen).
(Coloured Plate XIV. Plate VIII, Fig. 2).

References : — Listen, Ind. Med. Gaz., December, 1901, p. 441 ; Theobald, Monog.

Culic., Yol. Ill, p. 48.

Synonym, Myzomyia Turkhudi (Theboald).

A large brown mosquito with characteristic black tips to the
palpi.

The tips of the palpi are black-scaled. There are, however,
three white bands on each palp. One circle is situated on the
middle of the terminal segment, while the other two are situated at
the anterior extremities of the second and third segments.

The proboscis is covered with dark scales, but is yellow at its tip.

The head is covered with brown and white scales. There is a
small frontal tuft of white hairs.

The thorax is covered with long thin golden and white hair-
like scales. The scales are so arranged as to show a median and
two less distinct dark longitudinal markings. The lateral aspects

["5

Anopheles turkhudi.

of the thorax are covered with brown scales. The abdomen is of a
dark olive green colour, and is covered with many light yellow hairs.
The wings are covered with long spindle-shaped scales.

The costa shows six white-scaled portions ; one of these is
apical.

The first longitudinal vein has white areas corresponding with
the outer five white areas on the costa. There is, however, in
addition, a small white-scaled interruption at the position of the
transverse vein.

The second longitudinal vein has five white-scaled areas ; two
at the position of the transverse veins, one at the bifurcation of the
vein and two on its anterior branch.

The third long vein has two light-scaled portions — one at the
position of the transverse veins, and the other immediately below
the white area on the bifurcation of the second long vein.

The fourth long vein is white-scaled at its base, and has in addi-
tion a white-scaled portion at its bifurcation, and another at the
position of the transverse veins.

The trunk of the fifth longitudinal is white-scaled, except for
a single small dark-scaled portion. At its bifurcation it is dark-
scaled ; and its branches are dark-scaled, except for one white-scaled
portion on each.

The sixth long vein has a single white-scaled area. The wing
fringe is interrupted by light scales at the distal extremities of all
the veins except the sixth.

The legs are dark-scaled throughout, except for a few yellow-
ish-white scales at the distal extremities of the femora and tibiae.

The extremities of the claspers of the male genitalia are of a
different shape to those in most other " anopheles."

Characters of the eggs and larvce. — Dr. Christophers has shown
that the eggs of this species are very peculiar in that the lateral floats
are exceedingly rudimentary and sometimes are scarcely to be made
out at all (Fig. 8, p. 39).

The larvae are also peculiar in that there are, as a rule, no pal-
mate hairs on the first three abdominal segments, these hairs being
borne only by the fourth to the seventh segments. For this reason
the larvae rest at the surface of the water in a somewhat oblique
attitude. The shape of the palmate hairs is shown in the figure ; in

Anopheles lindesayi.

addition to the two pairs of unbranched frontal hairs, a third pair of
simple hairs ("Posterior" hairs) project over the mouth parts behind
and between the frontal hairs.

Habitat and observations. — First found at Ellichpur in the
Berars. It also occurs in the Central Provinces ( Nagpur), in
Aurungabad (Hyderabad State), and in Kashmir.

The black-tipped palpi serve to distinguish this species from
all other Indian "anopheles" except nagpori, which, however,
is easily recognised by the presence of white hind tarsi.

It has been proved that, under experimental conditions, the
parasites of human malaria are capable of developing in this species.

GROUP VIII.

Types : — A. lindesayi and A. gigas.
19. ANOPHELES LINDESAYI (Giles).

(Coloured Plate XV).

Reference : — Giles, Handbook Mosq., 1st Ed., p. 166.
Anopheles Lindesayii (Theobald).

A dark brown mosquito with one large yellowish-white spot
on its wing near the apex and with thin black unhanded palpi. The
femora of the hind legs are marked with a characteristic long
white band.

Palpi entirely black, covered with short dark scales. Pro-
boscis black.

Head for the most part covered with dark scales, except over
the occiput where they are white.

Thorax covered with hair-like scales ; the dorsal aspect of the
thorax is of a light grey colour ; the lateral aspects are darker.

Scutellum v-ith a few scales and long bristles. Abdomen
black, covered with many long hairs. Wings with the veins cover-
ed with narrow long spindle-shaped scales.

Costa dark brown ; white at its termination.

First longitudinal vein dark brown except at its distal extre-
mity, where it is covered with yellowish white scales.

Second long vein entirety covered with brown scales, except
at the tip of each of the branches, where there are light scales.

[117

Anopheles gigas.

There is an additional white spot on the posterior branch near its
termination.

Third long vein with light scales near its inner extremity, and
also at its outer extremity ; otherwise covered with dark brown scales.

Fourth long vein covered with dark scales except for a light
spot on each of its branches ; the spot on the anterior branch is on
the middle of its course ; the spot on the posterior branch is at its
outer extremity.

Fifth long vein for the most part covered with dark scales,
except at its bifurcation where there are white scales. There are,
in addition, two light-scaled areas on its anterior branch.

Sixth long vein covered with dark scales except at its tip.

The wing fringe is interrupted by light scales.

The legs are for the most part covered with dark scales.
There are light scales at the distal extremities of the femora and
tibiae in all the legs. The hind femora have a characteristic broad
white band in the middle third of their length.

Characters of the larva. — Dr. Christophers states that the
larval antennae of this species are provided with a small rudimentary
branched hair somewhat like the branched hair on the antennae of
the larvae of barbirostris and nigerrimus. The frontal hairs are
simple and unbranched. There are no thoracic palmate hairs.

Habitat and observations. — This species appears to occur only
in hill districts. A few specimens were obtained at Reneghat
(Bengal) at an elevation of about 4,000 feet. It also occurs at
Bakloh (6,000 feet) in the Punjab, and at Naini Tal (6,500 feet).

20. ANOPHELES GIGAS (Giles).
(Ento. Mo. Mag., Vol. XXXVII, 1901, p. 196.)

Anopheles gigas (Theobald).

We regret that we have not been able to obtain specimens of
this mosquito. The following description is extracted from Mr.
Theobald's Monograph, Vol. II, p. 308.

Thorax fawn-coloured in the middle, dark brown on each side ;
abdomen dark brown ; legs dark brown with basal pale bands, pale
at the base ; wings with two large black spots along the costa and
black patches on the wing field ; fringe with pale areas.

Anopheles gigas.

Head brown grey in the middle ; proboscis long, deep brown,
curved ; palpi long with deep brcfwn scales, rather thin, not quite
as long as the proboscis ; antennae pale brown.

Thorax pale fawn-coloured in the middle ; dark rich brown on
each side, and a narrow thin dark median line ; the middle area with
frosty grey tomentum and narrow curved hairs ; scutellum pale ;
metanotum chestnut brown.

Abdomen deep brown with long golden hairs. Wings large
the costa black with three creamy spots, the black forming two
large black spots which extend over the first long vein and upper
branch of the second and base of the fork cell, there is also a black
patch on the lower branch of the sub-marginal cell, and two on the
stem, one basal ; a small dark patch at the base of the third long
vein, all the rest creamy-yellow ; a black patch at the apex of each
branch of the second posterior cell and another at the base of the
cell, greater part of the stem dark-scaled ; three black patches, the
median one large, on the upper branch of the fifth vein, base of the
fork dark, and another dark patch towards the base of the vein ;
sixth vein mostly black-scaled with a median pale patch ; fringe
pale where the veins join the border of the wing, except at the
ends of the fifth vein, which have no pale fringe spot, but a pale
area between the two branches ; supernumerary cross vein nearer
the apex of the wing than the mid-cross vein, the posterior cross
vein nearly three times its length distant from the mid-cross vein.
Halteres with dense black knob.

Legs long, with coxae and trochanters pale, almost white, re-
mainder deep brown with traces of basal pale banding especially to
the metatarsi and tarsi of the hind legs.

Habitat. — Coonoor, Nilgherri Hills, India, 6,000 feet.

GROUP IX.

Types : — A. aitkeni and A. immaculatus.

21. ANOPHELES AITKENI (James).
(Figure facing page 120, Plate IX, Fig. 3.)
Reference : — Theobald, Monog. Culicid., Vol. Ill, p. 22.
A small mosquito of a uniformly dark colour and with un-
spotted wings.

[119

Anopheles aitkeni.

Head black, with a few white spindle-shaped scales in front
and long narrow deep brown upright-forked scales behind. There
is no marked frontal tuft of hairs. Palpi covered with small black
scales and with no trace of banding. Antennae with long black
hairs at the joints. Proboscis brown.

Thorax dark brown, with long brown hairs but without scales.
Scutellum with long dark bristles.

Abdomen black, without scales, but with many long brown hairs.

Wings with the veins completely clothed with dark scales.
The first sub-marginal cell is much longer and narrower than the
second posterior cell.

The supernumerary cross vein is internal to the mid-cross vein.
Posterior cross vein internal to mid-cross vein and nearly opposite
supernumerary cross vein.

Legs brown throughout. The coxae are pale. There is no
trace of banding at any of the joints. The hind first tarsal segment
(metatarsus) is longer than the tibia.

Characters of the larva 'Fig. facing text 1. — Median frontal
hairs stout and bifurcated like the prongs of a pitchfork ; external
angular hairs simple, short, and unbranched. Palmate hairs well-
developed on the second to the seventh segments. Terminal filament
of each leaflet not sharply marked off from the body and rather short.

Habitat and observations. — Collected near Karwar by Dr.
Cogill, and on the hills above Karwar (Goa frontier) by Mr. Aitken.

This mosquito very closely resembles bifurcatus and algeriensis,
but according to Mr. Theobald it can be at once distinguished from
those species by the striking dissimilarity in the size of the fork cells.

22. ANOPHELES IMMACDLATUS (Theobald).

References : — Theobald, Monog. Culicid., Vol. Ill, p. 23 ; James, " Malaria in

India," p. 45.
Anopheles immaculatns (Theobald).

The single representative of this species was caught by Dr.
Stephens, of the Royal Society's Malaria Commission, at Bnnur,
near Madras. The following is Mr. Theobald's description :-—

Thorax ashy-brown, with darker marks and pale hairs ; abdomen
brown, with golden hairs, most dense apically ; palpi shorter than
usual, brown, becoming ochraceous to almost white apically ; legs

1 20]

PLATE XIII.

f\

>~°A /

Ny

PLATE XIII. Anopheles aitleni ; showing the head of the larva (note the "basal hnirs '
external to the antennae), a palmate liair, and the outline of the wing.

4 nopheles immaculatus .

brown, with ochraceous reflections, the tarsi dark in some lights,
with pale apical bands ; wings with ochraceous veins, unspotted.

Head dark brown, with grey upright-forked scales in front,
ochraceous and darker ones behind, while narrow-curved scales in
front form a more or less projecting mass, beneath which arises
a tuft of long white hair-like scales ; antennse brown, the basal
joint bright testaceous, the next few joints with pale scales ; palpi
short for an Anopheles, rather thick, covered with dense brown,
grey and ochraceous scales, the brown scales basal, the others form-
ing most of the apical covering ; proboscis about the same length
as the palpi, ochraceous brown with a paler tip.

Thorax ashy-brown with slaty reflections, with darker longi-
tudinal lines, one being median, the surface with pale golden, hair-
like curved scales, a tuft of pale scales projecting over the head in
front ; scutellum with narrow-curved, hair-like, pale golden scales,
and brown border bristles ; metanotum deep brown.

Abdomen deep brown to black, with golden hairs, which are
very dense on the apical segments.

Legs ochraceous with brown scales, scantily set on the femora,
so that they appear dull ochraceous ; the tarsi are darker, especially
on the hind legs, which have the apices of the joints banded with
ochraceous ; to some extent this banding may be seen in the fore and
mid legs ; ungues equal, simple, deep brown, large for an Anopheles.

Wings unspotted, with yellowish veins and pallid scales ; fork-
cells rather short, the first sub-marginal longer and narrower than
the second posterior cell, their bases nearly level, the stems longer
than the cells ; supernumerary and mid-cross veins apparently in
one line, the posterior cross-vein about three times its own length
behind the mid-cross vein ; halteres ochraceous.

Habitat and observations. — Mr. Theobald says the specimen
is " evidently from Goa," and that it was given to him by Captain
Liston. This is incorrect. It was captured at Ennur — a small
village on the East Coast about ten miles from Madras — and sent
to Mr. Theobald by Dr. Stephens.

The markings on the palpi must have faded somewhat by the time
the specimen reached Mr. Theobald, for in the fresh state three white
bands were distinctly present — a very broad apical one extending over
nearly the outer half of each palp, and two very narrow basal ones.

Anopheles culiciformis.

GROUP X.

Type : — A. culiciformis.
23. ANOPHELES CULICIFORMIS (sp. n.)

(Figure facing page 122).

This is a rather large, brown "anopheles," for some time
confounded with the much smaller A. aitkeni till separated by
Dr. Cogill by its very markedly " culex" like attitude, by the
relative position of the transverse veins, and particularly by the
marked difference in the structure of the larva. This mosquito
might be Theobald's Stethomyia nimba, but he states that in that
mosquito the halteres have a pallid stem and fuscous knob, while
this species has a black knob covered with brown scales. Another
important difference is found in the characters of the male insect,
for while Theobald states that S. nimba has the fore ungues in the
male unequal, the larger uniserrated, Dr. Cogill has drawn our
attention to the fact that there is only one claw on each fore leg of
culiciformis and that has only a single tooth. In all other respects
this mosquito conforms with Theobald's description of S. nimba.

The palpi are entirely covered with brown scales ; without any
bands ; rather shorter than the proboscis.

The head is chiefly covered with brown upright-forked scales,
but there are a few white spindle-shaped scales in the middle line in
front ; there is no distinct frontal tuft of hairs. There are rather
more numerous and stronger brown hair-like bristles around the eyes
and on the front of the head than is usual in other " Anopheles."
Thorax covered with a few white hair-like scales and many long
brown bristles. Prothoracic lobes distinctly mammilated as in
Theobald's Stethomyia nimba. Scutellum with long brown bristles ;
in the middle there are a few short scale-like bristles.

Abdomen brown, covered with numerous fine golden aod coarse
brown hairs.

Wings unspotted and covered with rather broad spindle-shaped
scales approximating in shape to those found on nigerrimus. Vena-
tion as in other " Anopheles." Transverse veins almost in one line.

Halteres with light stem and dark brown knob covered with
brown scales.

Legs long and thin, entirely brown and covered with scales.
I22J

PLATE XV

PLATE XV. The larva of A. cidiclformis ; showing the characteristic " basal
hairs " external to the antennae, the absence of palmate hairs on the
first abdominal segment, and the shape of the palmate hair leaflet*.

Anopheles culiciformis.

The male of this mosquito differs from all other " anopheles"
in that the claws on the fore legs are single and uniserrated. There
are structural differences too in the larva which differentiate this
mosquito from all others.

Characters of the larva (Fig. facing page 122). — The frontal
hairs are simple and unbranched ; the median hairs are very
close together and long ; the external angular very short. The
most characteristic and constant feature of this larva is the peculiar
structure of the " basal hair." In most " anopheles" this hair
is much branched ; in the larva of this species it is made up of a
long stalk covered with a few hairs ; the extremity appears as if
jointed to the stalk, and is somewhat swollen and covered with a
corona of fine hairs. The next point in which this larva differs
from other " anopheles" is that the " balancer" hair on the third
abdominal segment is simple and unbranched. A third peculiarity
is found in the fact that well-developed palmate hairs are found on
all the abdominal segments except the first and last, and there is
also a pair on the thorax. The shape of the leaflets of each pal-
mate hair most nearly resembles that of the leaflets of the palmate
hairs of the larvae of barbirostris. There is no well defined blade
as contrasted with the terminal filament in each leaflet.

Habitat and observations. — This mosquito was bred from larvae
collected near Karwar, in the Bombay Presidency, by Dr. Cogill.
There seems to us to be no doubt that it would be placed by
Mr. Theobald in his genus Stethomyia.

[123

GENERAL INDEX.

A.

Abdomen, of larva, 8, 9 ; of adult insect, 13, 14 ; scale structure of, 17 ; examination
of, 29.

Aedeomyia, genus, 17.

Aedeomyina, sub-family, 5, 6, 17.

Aestivation, 55.

Air-sacs, 12.

Aldrichia, genus, 18, 19, 61, 112 ; error, 17, 19, 34, 112.

Anal cell of wing, 15.

" Anopheles," 6 ; eggs of, 7, 8, 38 ; larva of, 8, 9, 10, 11, 35, 36 ; pupa of, 13 ; collec-
tion of, 22 ; mounting of adults, 28 ; of larvae, 34 ; examination of, 28 ;
identification of, 30, 34, 38 ; synoptic table of adults, 32 ; of larvae, 37 ;
differences between male and female, 13 ; scale structure of, 16, 17, 18
19 ; classification of, 18, 19, 59 ; distribution and prevalence of, 41 ;
relative abundance of, 43, 53, 54 ; habits of, 41 ; distance of flight of,
45 ; hibernation of, 44 ; migration of, 45 ; mode of spread of, 47 ;
breeding grounds of, 48 ; food of adults, 54 ; of larvae, 57 ; nocturnal
habits of, 54 ; as carriers of filarise, 55, 81 ; length of life of, 55 ; swarm-
ing of, 55 ; position when resting, 56 ; in relation to malaria, 4::, 47, 48,
53, 54.

Anopheles, genus, 18, 19, 20, 64.

Anophelina, sub-family, 5, 6, 18.

Antennae of larva, 9, 36 ; of adult, 13 ; in identification, 13, 28.

Arribalzagia, genus, 18.

B.

Balancer hair, 123.

Balancers, 3.

Basal hair, 10, 36, 123.

Bot-flies, 4.

Blood worms, 12.

Blue bottle flies, 4.

Breeding grounds, as factors in distribution of species, 42 ; as factors in prevalence of

adult insects, 43 ; as factors in distance of flight of adults, 46 ; selection of,

by different species, 48 ; of Indian species, 50.
Breeding out larvae, 25.

c.

Cecidomyidoe, 4 ; characters of, 5.
Cellia, genus, 18, 65.
Cells of wing, 15.

[125

General Index.

Chironomidae, 4, 5 ; larva of, 12.

Christia, genus, 18 19.

Classification of Culiddae, 5 ; of " anopheles," 18, 59 ; scale structure as a basis of, 17,
63, 97, 100, 103, 112, 114 ; entomologists and, 60 ; medical men and, 63, 64, 67 ;
individual differences, monstrosities and varieties in, 60 ; dimorphism in, 61 ;
as an aid in identification of species, 20, 64 ; habits and pathological signi-
ficance in, 64, 66 ; into groups of closely allied forms, 66.

Climate, effect on distribution of " anopheles, " 42.

Clypeal hairs, 10, 35.

Clypeus of larva, 10 ; of adult insect, 13.

Cocades, 68.

Collection of adult mosquitoes, 22 ; of larvae, 25 ; of eggs, 38.

Costa, 14.

Coxa, 14.

Corethra, genus, eggs of, 7 ; larva of, 12.

Corethrina, sub-family, 5, 6, 1 2.

Cross veins, 15.

" Culex," 6 ; eggs of, 6 ; larva of, 8, 9, 10, 11 ; pupa of, 13 ; scale structure of, 17 ;
position when resting, 57.

Culex, genus, 7, 9, 14, 17.

Culicidcet family, 3, 4 ; classification of, 5.

Culicina, sub-family, 5, 6, 7.

Cycloleppteron, genus, 18.

Cyclorrhapha, group, 4.

D.

Daddy-long-legs, 4.

Dimorphism, 61.

Dipping for larvae, 25.

Diptera, order of, 3, 4.

Distance of flight of " anopheles," 45.

Dispersal of " anopheles," 47.

Distinctions between mosquitoes and other flies, 4.

Distribution of " anopheles," 41, 42.

Dixa, larva of, 12.

" Domestic " species, 22, 53.

Eggs, hatching of, 4 ; differences between " culex " and " anopheles," 6 ; rafts of, 7 ;

of Stegomyia, Panoplites, Psoropkora, Janthinsoma, 7 ; of " anopheles," 8 ;

collection, examination and identification of, 38 ; duration of egg-stage, 57 ;

resistance to drying, 57 ; laid on mud, 57.
Entomologists and classification, 5, 60.
Ephemera, larva of, i2.
Epipharynx, 13.
Examination of eggs, 38 ; of larvae, 34 ; of mosquitoea, 28, 33.

P.

Families mistaken for mosquitoes, 4.
Feeding brushes, 10.

126]

General Index.

Femur, 14.

Flesh flies, 4.

Flies, differences between mosquitoes and, 4.

Flight of " anopheles," 44.

Floats of eggs, 8, 38.

Food of adult " anopheles," 54 ; of larvae, 57 ; as a factor in distribution of

"anopheles," 42 ; as a factor in distance of flight, 46.
Frill of " anopheles " eggs, 8, 39.
Fringe, wing, 16.

Frontal hairs of larva, 10, 35, 37 ; tuft, 29.
Fungus-midges, 4.

GK

Gad-flies, 6.
Gall-midges, 4.

Genitalia, 14 ; mounting of, 28 ; examination of, 30.
Genus, definition of, 59.
Geographical races, 63.
Gnats, 3.

Green bottle flies, 4.

Groups, by colour markings, 30 ; by breeding grounds, 50 ; by habits and pathological
significance, 31 ; in systematic classification, 59 ; of closely allied forms, 66.

H.

Hairs, important larval, 10, 35, 36.
Halteres, 3, 14, 29 ; scales on, 17.
Haunts of adult " anopheles," 22, 24.
Heptaphlebomyina, sub-family, 5, 6, 61.
Hibernation of adults and larvae, 44, 55, 56, 58.
Horse flies, 4.
House flies, 4.
Hover flies, 4.
Hypopharynx, 13.

I.

Identification of adult " anopheles," 30 ; of larvae, 34 ; of eggs, 38 ; synoptic tables

for, 32, 37 ; larval hairs as an aid in, 10 ; classification as an aid in, 64.
Imago, 4.

Individual differences, 59.
Insecta, 3.

Janthinsoma, genus, eggs of, 7.
Joblotina, sub-family, 5, 6, 17.

L.

Labium, 13.
Labrum, 13.
Larvae, 3, 4 ; description of, 8 ; differences between " culex " and " anopheles," 8, 9 ;

collection of, 25 ; mounting of, 34 ; examination and identification of, 34 ;

movements in water, 10 ; method of feeding, 10 ; food of " anopheles, " 57 ;

[127

General Index.

important hairs on, 10, 35 ; head pattern of, 36 ; resistance to drying, 58 ;
duration of larval stage, 58 ; hibernation of, 58 ; of Chironnntus, Ephemera
and Dixa, 12 ; synoptic table of Indian "anopheles," 37.

Legs, examination of, 30, 33 ; segments of which composed, 14 ; scales on, 17.

Length of life of " anopheles, " 55.

Local forms, 63.

M.

Malaria, influence of species of " anopheles, " 42, 67, 71 ; relative abundance of
" anopheles " in relation to, 53, 54 ; habits of " anopheles " in relation to
prevention of, 47.

Mandibles, 10, 13.

Mansonia, genus, 18.

Marginal transverse vein, 15.

Maxillae, 10, 13.

Megarhinina, sub-family, 5, 6.

Meso thorax, 14.

Metamorphosis, definition of, 3 ; stages of, in mosquitoes, 4, 6.

Metanotum, 14, 29.

Metatarsus, 14.

Mid-cross vein, 15.

Midges, 4.

Migration of " anopheles, " 45.

Monstrosities, 60, 61.

Mosquitoes, general account of, 3 ; differences between other flies and, 4 ; classifica-
tion of, 5 ; larvae of, 4 ; adult insect, 13 ; differences between male and
female, 13 ; collection of, 22 ; mounting of, 26 ; preservation of, 26 ; exa-
mination of, 28 ; differences between " anopheles " and other kinds, 14.

Mounting of adult '' anopheles, " 26 ; of larvae, 34.

Mouth parts of adult mosquito, 13.

Movements of larvae in water, 10.

Mucidus, wing scales of, 17.

Muscidce, 4.

Mycetophilidce, 4.

Myzomyia, genus, 18, 19, 20, 66.

Myzorhynchus, genus, 18, 19.

N.

Nape, 13.

Nocturnal habits of " anopheles," 54.
Nyrnpha, see Pupa.
Nyssorhynchus, genus, 18, 19, 21, 65

o

Objections to Mr. Theobald's classification of "anopheles," 19,63,82,97, 100,103,

112, 114.
Occiput, 13.
Oestridce, 4.
Order, definition of, 59.

128]

General Index.

Orthorrhapha group, 4.
Ovum, 6.
Owl midges, 4.

P

Palmate hairs of larva, 9, 35 .

Palpi, length of as basis of, classification, 5 ; of adult insect, 14 ; in identification,

28, 30, 31 ; scale structure, 17.

Panoplites, genus, 18 ; eggs of, 7 ; wing scales of, 17, 18 ; palpi of, 14.
Phantom larvae, 12.
Posterior cross-vein, 15.
Posterior hair of larva, 10, 36 .
Preservation of mosquitoes, 27.
Prevalence of " anopheles," 41, 44.
Pro-thoracic lobes, 18, 122.
Proboscis, 4 ; scale structure, 17.
Psorophora, genus, eggs of, 7.
Psyckodidos, 4 ; characters of, 5.
Pupa, 4, 12 ; distinctions between "eulex" and " anopheles,"13 ; breathing horns of,

as a means of distinguishing species, 68.
Pupa-case, mode of opening of, 4.
Pyretopkorus, genus, 18, 19, 66.

Respiratory tubes of larvse, 8, 12.
Rim of " anopheles " eggs, 8, 39.

s

Sabethes, leg scales of, 17.

Sandflies, 4.

Scales, different forms of, 16 ; on wing veins, 4 ; as a basis of classification, 17, 18, 19»

20,21,63,97,100,103,112, 114.
Scutellum, 14, 29.
Seasonal prevalence, 43.
" Shaving brushes," 35.
Simulidce, 4, 5.

Siphon tube of larvse^S ; of Stegomyia, Culex and Tceniorhynchus larvae, 9.
Siphonic index, 9.

Species, definition of, 59 ; differentiation of, 62.
Speckling of palpi and legs, 29, 30, 33.
Spiracles, 13.
Splitting of pupa-case, 4.

Stegomyia, eggs of, 7 ; larva of, 9 ; characters of palpi, 14 ; scale structure of, 17.
Stethomyia, genus, 18, 122.

Streams and canals as factors in spread of " anopheles," 47.
Subcostal vein, 15.
Supernumerary cross-vein, 15.
Swarming of " anopheles," 55.
Synoptic tables, 32, 37.
Syrphidce, 4.

General Index.
T.

Tabanidoe, 4.

Tceniorhynchus, eggs of, 7 ; larva of, 9 ; wing scales of, 17, 18.

Tarsal joints, 14, 33.

Tarsal segments, 14, 30, 33.

Test-pool experiment, 52.

"Iheobald, classification of mosquitoes, 5 ; of "anopheles," 18, 19, 20, 21, 63, 64, 65,

97, 100, 103, 112, 114 ; differentiation of species, 62.

Thorax of larvae, 10 ; of adult insect, 13, 14 ; examination of, 29 ; scale structure, 18
Tibia, 14.
Tipulidce, 4, 5.
Tracheae of larvae, 8, 12.
Transverse veins, 15, 29, 62.
Trochanter, 14.
Tsetse flies, 4.

Tube for preserving mosquitoes, 27.
Tuft, frontal, 29.

u.

Ungues, mounting of, 28 ; examination of, 30.

V.

Veins of wings, arrangement of, 4, 14.
Variation, 62 ; in frontal hairs of larvae, 37.
Varieties, 60, 66.

w.

Warble flies, 4.

Whorl organs, 10, 35.

Wild species of "anopheles," 24, 53.

Wing, fringe, 16 ; markings, 29 ; scales, 17, veins, 14 ; mounting of, 28.

Winter, methods by which mosquitoes tide over, 44.

130]

INDEX OF SPECIES.

The principal reference to each species is printed in heavier type.

A

aitkeni, 19,32, 37, 42, 56, 73, 119.

albirostris, 7 1 .
alboannulatus, 81.
albotoeniatus, 68.
algeriensis, 42, 120.

B

bancroftii, 68.

barbirostris, 19, 32, 36, 37, 39, 41, 51, 53, 68, 77, 79.

bifurcate, 42, 120.

c

christophersi, 106, 103.

coatalis, 72, 112.

culicifacies, 19, 20, 21, 23, 24, 32, 33, 37, 39, 41, 42, 44, 45, 49, 50, 54, 56, 58, 60,

62, 66, 70, 101, 103, 106, 112.
culiciformis, 10, 32, 36, 56, 73, 122.

E.

elegans, 19, 32, 37, 42, 69, 82.
error, 17, 19, 34, 112.

P.

fluviatilis, 103, 106.

fuliginosus, 19, 32, 33, 37, 40, 41, 44, 45, 46, 47, 49, 51, 53, 54, 58, 61, 69, 89, 91,

95, 100.
funestus, 42, 60, 62, 67, 71, 106.

G

gigas, 19, 21, 32, 42, 72, 117, 118.

immacidatns, 19, 32, 119, 120.
i.ndica, 109.

mdiensf*, 19, 81 ; variety, 97.

J.

jameri, 19, 32, 33, 51, 89, 93, 96, 100.

jeyp&riensis, 10, 19, 20, 32, 33, 36, 37, 42, 70, 101, 105, 108.

Index of Species.
K

karwari, 10, 19, 32, 37, 89, 100.

L

leptomeres, 34, 71.

leucophyrus, 19, 82, 85.

lindesayi, 19, 32, 37, 42, 72, 117.

listoni, 19, 20, 32, 33, 37, 39, 42, 48, 50, 54, 62, 67, 101, 103, 108.

M

maculatus, 19, 21, 32, 37, 42, 52, 70, 89, 91, 99, 100, 115.

macidipalpis, 19, 29, 32, 33, 37, 41, 89, 95, 100.

maculipennis, 54, 55.

malayensis, 68.

mauritianus, 68.

metaboles, 113, 115

minutus, 19, 34, 60, 68, 79, 81.

N

nagpori, 32, 72, 101, 117.

nigerrimus, 19, 37, 39, 41, 48, 51, 68, 77, 79.

nimba, 121.

P

paludis, 68.

pseudopictus, 68, 81.

pulcheirimus, 19, 29, 32, 37, 40, 41, 44, 45, 69, 86, 114.

punctulatus, 32, 69, 82, 84 112.

R.

rhodesiensis, 60, 62, 71.

rotri, 19, 20, 21, 23, 31, 32, 36, 37, 40, 41, 42, 44, 45, 46, 48, 49, 51, 53, 54, 56, 58, 61r
66, 69, 71, 109, 112.

s.

smen&is, 17, 19, 32, 68, 81.

stepensi, 19, 21, 29, 31, 32, 36, 37, 40, 42, 45; 49, 51, 69, 71, 89, 109, 111, 113, 115.

T.

tenebrosus, 68.

tJieobaldi, 19, 32, 37, 70, 89, 95, 97, 100.

turkhiidi, 10, 19, 21, 32, 36, 40, 72, 115

u

umbrosus, 68.

V

vanus, 34, 81.

w

willmori, 19, 21, 32, 69, 86, 88, 114.

132]

Claws

— Tar sal
Seqmenks

Anterior

Transverse
veins

Middte Leo

Proboscis

Antenna

Occiput

K IP

'4th Beg?

f '

Fro/it al

—tuft

1st Loncjikudin al I "tin
2nd Longitudinal

I »» Anterior branch
I f >» Posterior „

\ \ \ 3/v/ Lonqihtdin a I
\ \ \ tJi

Femur

Thora,X-

Sub -costal Vein

Scutellum

Hotter

vipositor

Anterior 6
Posterior >»

\\\ Anterior branch
\ \ ^ Posterior >•

^ 5 tli Lonqitudina t

'6(h Longitudinal,
j

Posteriori

DESCRIPTIVE DIAGRAM
ANOPHELES 9

D.A.Turkhud

COLOURED PLATE No. II.

Anopheles (Myzorhynchus)
barbirostris.

Description on page 77.

\\

(surbn yihoxyM )

\

•

i

ANOPHELES BARBIROSTRIS

D.A.Turkhud.M.B.

\

\

COLOURED PLATE No. III.

Anopheles (Myzorhynchus)
nigerrimus.

Description on page 79.

A\\ AV/\ S.Tk.YV AV 3

eabriqortA

V

J

/

I

ANOPHELES NIGERiMUS

\

D. A Turkhud M.B.

\
/

COLOURED PLATE No. IV.

Anopheles (Cellia) pulcherrimus.

Description on page 86.

-.'A, :YYUY\

riqon

X X

ANOPHELES PULCHERRIMUS

B.A.Turkhud MB.

COLOURED PLATE N». V.

Anopheles (Nyssorhynchus)
fuliginosus.

Description on page .91.

, *\Vv\*\ (XA'A^O.

• -. • ' '••>-.'

COLOURED PLATE No. VI.

Anopheles ( Nyssorhynchus) jamesi.

Description on page 93.

vi <AA. 3V\KA<\ cvv/w

iaarn£[

r

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ANOPHELES JAMESI!

D.A.Turkhud M.B.

COLOURED PLATE No. VII.

Anopheles (Nyssorhynchus)
maculipalpis.

Description on page 95.-

AY

)

«*« •***»«, -^s.

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ANOPHELES MACULIPALPIS

D.A.TurkKud Vi.B.

COLOURED PLATE No. VIII.

Anopheles (Nyssorhynchus)
theobaldi.

Description on page 97.

j

>:

ANOPHELES THEOBALDI
9

D.A.Turkhud M.B.

COLOURED PLATE No. IX.

Anopheles (Pyretophorus)
jeyporiensis.

Description on page 101.

-7A .v

1 01 9gfiq no noijqi,

/

/

V

/

ANOPHELES JEYPORIENSIS

¥

D.A.Turkhud.M.B.

\

\

\

COLOURED PLATE No. X.

Anopheles (Myzomyia) listoni.

Synonym, Anopheles fluviatilis.

Description on page 103.

COLOURED PLATE No. XI.

Anopheles (Myzomyia) culicifacies,

Description on page 106

ANOPHELES CULICIFACIES
9

D.A.Turkhud M.B.

COLOURED PLATE No. XI 7.

Anopheles (Myzomyia) rossi.

Description on page 109.

ikj

ANOPHELES ROSSI!
9

D.A.Turkhud. M.B.

COLOURED PLATE No. XIII.

Anopheles (Nyssorhynchus)
stephensi.

Description on page 113.

\\VA AV/.

1 1 s no

ANOPHELES STEPHEN SI

COLOURED PLATE No. XIV.

Anopheles (Myzomyia) turkhudi.

Description on page 115.

HVA <

(

) g'

nu nuilt.

\

ANOPHELES TURKHUDI

/

D.A.Turkhud M.B.

COLOURED PLATE No. XV.

Anopheles (Anopheles) lindesayi.

Description on page 117.

ANOPHELES LINDESAI
9

D.A.Turkhud M.B.