ART. 17. LARVAE OF HOLAECTIC TIGER-BEETLES HAMILTON. 11 



In the eighth segment (figs. 1 and 42) the eiisternum, sternelliim, 

 and coxal lobes are fused to form a single sclerite. On the ninth 

 segment (fig. 42) this chitinized area includes the sclerite of the 

 hypopleurum. The caudal margin of this fused sclerite bears four 

 setae in a transverse row on each side of the meson. The tenth seg- 

 ment (figs. 1 and 42) is greatly reduced in size, the sclerites of the 

 tergum, pleurum, and sternum are fused to form a ring, and the 

 whole structure has the character of what Kemner calls a pygofod. 



The tergum of the fifth abdominal segment (fig. 40) is produced 

 into a prominent hump bearing two distinct chitinized areas on each 

 side of the meson with two hooks between each of these sclerites. The 

 caudal sclerites are somewhat crescent-shaped, and their cephalic 

 margin is thickly studded with short, stout setae. The cephalic 

 sclerites are somewhat triangular with the base toward the meson. 

 They are not as heavily chitinized as the caudal sclerites and have 

 only about half as many setae, which are longer but not so stout. 

 Between these sclerites on each side of the meson are two hooks. 

 One of these hooks is long, sickle-shaped, extends cephalad with the 

 point outward, and usually bears two distinct setae at about the 

 middle. These hooks are named the " median hooks " {mh, fig. 40), 

 since in some of the other genera there is a third pair of hooks lat- 

 erad of these median hooks which have been named the " lata^al 

 hoohsy Mesad of each median hook is a shorter pointed hook. 

 These hooks are not curved and project dorso-cephalad. The distal 

 part is pointed and has a distinct shoulder which bears two promi- 

 nent setae. These hooks have been named " inner hooks " (ih, fig. 

 40). 



Spiracles are found on the first eight abdominal segments. They 

 are small, annular, and appear as brown spots on the lateral part 

 cf the tergum about one-third the distance from the cephalic margin 

 (fig. 1). The first abdominal pair are slightly larger than the 

 following pairs. 



SETAB. 



Larvae of the different instars were available for study in several 

 species of the genus Cicindela. This material was studied to de- 

 termine whether any relation existed between the number and 

 arrangement of the setae in the different instars of the same species 

 and the corresponding instars of different species. In the first larval 

 instar of the species studied it was found that a striking similarity 

 existed in the number and arrangement of the setae on the pronotum 

 and abdomen. These same setae were usually easily distinguished in 

 the second and third instars even though in some cases there was 

 a considerable number of setae added. For this reason the setae 

 present in the first larval instar have been designated as " primary 



