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general Principles as to Examination, Collection and 
Description of Mosquitoes. 
By G. F. Liecester, m.b., c.m., Edin. 
The following descriptions of mosquitoes are in the great majority of 
stances those of freshly killed specimens still showing their natuial 
lours. 
Most of the published descriptions, such as those in Theobald s 
onograph, are necessarily from dried specimens only, and there are 
nsiderable differences between the appearances observed in the fresh and 
jd specimens. 
From the entomological point of view a uniform system of examination 
dried specimens has advantages, but where the comparison can be made 
fresh specimens, specific characters can usually be more readily obseixed 
id certain errors avoided. 
The main changes in a dried mosquito are distortion, denudation and 
lange in colour. 
The distortion is often great, but varies in different species of 
losquitoes. Some, such as Anophelina, Melanoconion, etc., lose their 
iape and general aspect so much that their characteristic general appear- 
ace is lost. 
In others distortion of certain parts, as of the prothoracic lobes or the 
ead, takes place to such an extent that these parts when dried appear to 
ave characteristics which they do not possess in their natural condition. 
Denudation is a change that very commonly occurs in old specimens 
3 some extent. As the system of classification by cuticular appendages, 
articularly by the scales, introduced by Theobald, has proved of such 
alue for the differentation of genera and surpasses all other suggested 
aethods it is of the greatest importance that the specimens should be as 
ittie denuded as possible, 
Change in colour is of great importance for specific differences. 1 he 
:olouration of scaled insects such as these culicidae depends in part on the 
:olour of the part of the insect examined and in part on the colour of the 
scales clothing that part. 
Both these elements are affected by drying, but the changes in the 
:olouration of the scales are most affected and are of most importance. 
The colouration of many of these scales is a diffraction phenomenon 
ind varies with the incidence of the light as with most interruption colours. 
In the dried specimens these colours are always less vivid and are frequently 
ost. By the shrinking and distortion of the subjacent parts the inclination 
uf the scales to each other is altered, and consequently a different series of 
changes of colour produced to that found in the same region in an 
undistorted mosquito. This is particularly marked in the Megarhines, 
but is not confined to that class. 
The iridescence of the wings which forms so marked a feature of 
coloured plates of dried mosquitoes is only seen in a few species in the fresh 
condition. 
In many mosquitoes it is impossible to be certain how much of the 
colouration is due to interruption colours and how much to the real colour 
of the scales. In all loss of brilliancy occurs. Brilliant glossy blacks 
become dull black, or brown in old specimens whilst glistening white scales 
