50 Annals Entomological Society of America [Vol. XII, 



Larva: The larva is depressed, somewhat moniliform, pale 

 yellow in color, with dark brown on the head, prothorax and 

 ninth abdominal segment. When full-grown it averages 14-16 

 mm. in length, or when fully expanded, as much as 18 mm. 

 The head is subtriangular in outline, heavily chitinized and 

 nearly all dark brown as shown by the stippled portions in 

 Figs. 1 and 2. The pale lines seen on either side of the head 

 capsule (Figs. 1, 2, 3, 4) may indicate sutures, as the head 

 capsule will break along these lines when softened. If they 

 are sutures, their homology is doubtful; but as they are furrows 

 on the ectal surface and ridges on the ental they are perhaps 

 for the attachment of muscles. The head is much thinner 

 cephalad and laterad of these lines. Along the cephalic margin 

 of the head capsule are two small triangular projections and 

 four similar, but larger ones, along the lateral margin, making 

 it serrate. The lateral margin also has a prominent blunt 

 projection caudad of the serrations. The head is inserted into 

 the prothorax and may move laterad until this blunt projection 

 strikes the dark brown protuberance on the prothorax. The 

 head may also be moved dorsad and ventrad, and a prominent 

 projection like a condyle on the meson of each caudal margin 

 seems to facilitate these various movements and also prevents 

 the head from being shoved farther back into the prothorax. 

 The very dark line extending caudad from each cephalic pro- 

 jection (Figs. 3 and 4, t) marks the attachment of a strongly 

 chitinized bar to each surface, which is probably the tentorium. 

 Between these two bars at the cephalic end of the head is an 

 opening, the entrance into the buccal cavity. There are no 

 ocelli present. The head capsule is sparsely covered with very 

 minute setae. The appendages of the head are all retractile. 

 Their location is indicated in Fig. 3, where they are shown 

 extruded. Normally only the extreme tips of the mandibles 

 are visible and then only under high power, as all of these 

 structures are exceedingly minute. What I have considered 

 the antenna (Fig. 5) looks very like a maxilla but does not 

 seem to be in any way connected with the buccal cavity. Its 

 median projection at the distal end seems to be covered with 

 sensory structures and the lateral projection ends in at least 

 three finger-like projections. The structures articulated to the 

 tentorial bar are certainly the mandibles (Figs. 6 and 7, md). 

 Each moves in a horizontal plane and has one very long tendon. 



