ART. 17. LARVAE OF HOLARCTIC TIGER-BEETX,ES HAMILTON, 3 



the tropical species are arboreal and the larvae live in burrows in 

 the smaller twigs. The habits of the larvae have resulted in sev- 

 eral morphological adaptations. The head and pronotum are 

 strongly chitinized and highly colored on the dorsal part, the meso- 

 thorax and metathorax are much less chitinized and the abdomen is 

 membranous with chitinized, setaceous areas. The head and pro- 

 thorax are bent ventrad at an angle of about 45 degrees, the fifth 

 abdominal segment has a prominent projection on the dorsal aspect, 

 and the segments caudad of the fifth are curved ventrad. The 

 mature larvae vary from three-fourths to about two inches in length. 

 In describing the morphology of the larvae one species has been 

 taken as the type and only a few^ of the more characteristic varia- 

 tions in other species and genera have been considered. Cicindela 

 limhalis has been chosen for this purpose since it is one of the larger 

 and more generalized species of the Cicindela and is widely dis- 

 tributed. 



HEAD. 



The head will be discussed under two divisions — the fixed parts or 

 the head capsule and the movable parts or the appendages. 



Flead capside. — The head capsule (figs. 5, 6, and 8) is heavily 

 chitinized, slightly concave on the dorsal aspect and strongly convex 

 on the ventral. The dorsal surface is bronze, with a bluish-green 

 luster, the ventral surface a light chestnut brown. The head capsule 

 is divided into two areas — the epicranium and the fronto-clypeo- 

 labral area — by the epicranial and frontal sutures. The epicranium 

 is divided into two halves — dorsally by the epicranial suture, ven- 

 trally by the gular suture. The epicranial suture (eps, fig. 8) is on 

 the dorso-meson and extends cephalad a short distance from the 

 occipital foramen. From this point a frontal suture (/s, fig. 8) 

 (r=arms of epicranial suture) extends cephalo-laterad as a sinuate 

 line to each antennal fossa. The gular suture {gus^ fig, 14) is on the 

 ventro-meson and extends cephalad from the occiput to the attach- 

 ment of the labium. 



The occiput {oc, figs. 5 and 8) is the narrow, slightly raised, band- 

 like sclerite extending around the caudal margin of the head capsule. 

 It is separated from the epicranium by the occipital suture (ocs, 

 fig. 8) and is strongly infolded on the ental surface. 



The epicranium consists of the following not distinctly defined 

 legions: Vertex, genae, and postgenae. The vertex {ve, figs. 5 and 

 8) occupies the dorsal and lateral parts of the epicranium and ex- 

 tends from the occiput to the frontal suture and the insertion of the 

 mandible. It includes within its boundaries the location of the 

 antennae and the ocelli. A prominent ridge extends cephalo-mesad 

 from each caudal ocellus to the frontal suture. The part of the head 



