i6 



being anterior. It is truncate where it touches the base of the mouth 

 papillae, slightly concave on the sides posteriorly, broadly rounded 

 anteriorly with two movable papillae on the anterior margin, each of 

 which bears a long spine, about equal in length to those borne on 

 the coxae of the two posterior pairs of legs. A curving suture on 

 each side of the anterior two-thirds of the plate divides it into three 

 parts, a long central piece with two side pieces. On the ventral sur- 

 face of the abdomen, underneath the operculum, is a pair of spines, 

 one on each side, about equal in length to those which arise at the 

 anterior end of the prostomial plate. These spines extend back- 

 ward, usually reaching nearly to the caudal margin of the body. 

 Anterior to and outside of the base of each of these spines there is 

 a small pore, which probably represents the opening of some gland, 

 as an amorphous, waxy (?) substance usually covers one or both 

 openings after the larva is two or three days old. 



Each antenna arises on a line about half way between the fore 

 coxae and the anterior margin of the body, and the length is between 

 one-half and two-thirds the width of the body. Each consists of four 

 segments, the basal one being short and stout ; the second twice as 

 long as the first, and more slender, reaching nearly to the margin of 

 the body between the third and fourth spines of each side, (the an- 

 tennae usually being directed in that direction) ; the third segment 

 very short, sub-globose, and bearing two or three short, stout spines ; 

 the fourth twice as long as the second, slender, its apical third bent 

 anteriorly, minutely spined, and with a larger and more conspicuous 

 spine arising at about two-thirds the distance toward the tip on the 

 posterior side, and another still larger one at the tip. Each ventral 

 eye is situated outside of and slightly behind the base of the an- 

 tenna of its respective side of the body. 



Segmentation from below is less distinct than from above. The 

 color of the larva is pale green, semi-transparent, with two internal 

 orange yellow bodies of irregular rounded form, situated one on each 

 side in the basal abdominal • region. These sometimes enclose a 

 clear area. The tracheal openings are ventral and very difficult to 

 distinguish in this instar, but their positions are marked by the gran- 

 ular appearance of the surrounding regions and by the abrupt termi- 

 nations of the main branches of the tracheal system, which maybe 

 more or less plainly seen in the semi-transparent body of a newly 



