Pe Sa CRE: 
ANATOMY OF THE MOUTH-PARTS AND OF THE SUCTORIAL 
APPARATUS OF CULE X.* 
BY GEORGE DIMMOCK, 
CAMBRIDGE, MASS. 
(With Plate I.) 
From early times the mosquitoes, Cu- 
lew of different species, have attracted 
the attention of mankind, and many at- 
tempts have been made to settle various 
points of their anatomy and life-history. 
Of their anatomy nothing is, perhaps, of 
more interest than a study of their pro- 
boscis. While the importance of the 
mouth-parts in the classification of insects 
remained undiscovered until Fabricius, in 
the last century, made them a basis for 
dividing the insects into classes and gen- 
era, considering that they furnished ‘* suf- 
ficient and constant characters, and far 
more natural genera ;”* and their homo- 
logical significance remained a mystery 
until Savigny,? in 1816, showed that the 
mouth-parts of all insects were reducible 
to the same general plan as those of 
* Extract, with additions and changes, from ‘ The 
anatomy of the mouth-parts and of the sucking ap- 
paratus of some diptera. Dissertation for the pur- 
pose of obtaining the philosophical doctorate at the 
Leipzig University, by George Dimmock, of Cam- 
bridge, Mass., U.S.A. Boston, A. Williams & Co., 
1881.” t.-p. cover, t.-p., 50 [+10] p., 4 pl., 24.5X 19, 
t 12.5 X17. 
1 Fabricius, J. C. Systema entomologiae, ... 1775. 
Preface. 
2 Savigny, J. C. Mémoires sur les animaux sans 
vertébres. I. partie, I. fascicule. Mém, I.-II.... 
1816. 
chewing insects, and that these mouth- 
parts were the serial homologs of locomo- 
tory appendages; yet, previous to the 
before-mentioned dates, a number of an- 
atomists, attracted, probably, as much by 
the minuteness of the objects and the 
difficulty of the work as by the popular 
interest which the mosquito excites, 
sought to complete our knowledge of the 
number, position and use of the mouth- 
parts of this insect. The earliest of 
these anatomists whose work is worthy 
of note is Swammerdamm, who studied 
Culex in 1668.% ‘The difficulty of the 
work which Swammerdamm undertook, 
with the crude apparatus at that time at 
his command, can be easily comprehen- 
ded when we consider that the proboscis 
of the female of most species of Culex 
has about the diameter of a hair from 
the human head, that is, a diameter of 
about one tenth of a millimetre; that it 
is composed (see pl. 1, fig. 8) for the 
most part of the sheath, within which 
are six so-called setae, later to be more 
fully described ; and that these setae are 
of transparent chitin, one of them being 
so transparent and delicate that it has of- 
3 Swammerdamm, J. Bybel der natuure .. . 1737- 
1738. [I have used the German editionof 1752.] 
