176 Journal New York Entomological Society. [Voi. xii. 



pair. Two other pairs of hairs or tufts occur upon the epistoma. 

 Usually they are very small, and in some forms, at least of the mature 

 larva, are absent altogether. One pair is situated farther forward and 

 nearer together than the " median " pair. The other pair is located 

 well back and near the epicranial suture, nearly opposite the eyes. 

 In the first stage these last two pairs of appendages are equally devel- 

 oped with the other three pairs which afterwards become so conspic- 

 uous. In the first stage the appendages all consist of single hairs, dif- 

 fering, however, in relative length and position in the different spe- 

 cies. One species only, in my experience, is an exception. In the first 

 stage of Culex triseriatus the pair of appendages nearest together con- 

 sist of fine hairs in twos. In the succeeding stages this pair develops 

 into tufts very similar to the outer pair. 



The three most highly developed pairs of epistomal appendages, 

 which I have termed the median, intermediate and outer pairs, are 

 present in all the species of Cidex larvge that I have examined. The 

 median and intermediate pairs develop very differently in the differ- 

 ent species. For example, in Culex territans they usually continue 

 as single hairs throughout the four stages, while in Culex restuans the 

 number of hairs in each appendage increases with each succeeding 

 stage. The outer pair consists of hairs in tufts in the last stage of all 

 the species I have examined. These tufts also differ in length, coarse- 

 ness and the number of hairs in the different species. In Culex can- 

 tans, for example, there are four or five coarse hairs in the tuft, while 

 in Culex territans there is an ample fan-shaped tuft of ten or twelve 

 hairs. In the first stage this outer pair of appendages, like the others, 

 is of single hairs. In the second stage these outer appendages usually 

 consist of two hairs, in some cases of three or four, and the number 

 of hairs increases in the third and fourth stages. As one would natu- 

 rally suppose, these appendages, like other characters, are subject to 

 some variation, but nevertheless are useful in determining species and 

 stages. My experience has been with a limited number of species, 

 but as far as I have gone each species has proved sufiftciently distinct 

 in these characters. 



The terminology "median," "intermediate" and "outer" pairs 

 of appendages was adopted when my descriptive work was first begun, 

 and has been retained for want of a better one. It is, however, 

 hardly satisfactory. 



Other hairs, or groups of hairs, also occur on various other parts 



