ART. 17. LARVAE OF HOLARCTIC TIGER-BEETLES HAMILTON. 5 



meet and fuse with the ventral arms of the tentorium. The dorsal 

 arjii^ {d.at,fig. 7) of the tentorium are fused with the anterior arms and, 

 on the inner surface of the head, are attached along the caudal part 

 of the suture separating the latero-clypeus from the clypeus. From 

 the middle of each fused arm a free part projects dorso-caudad. 

 These, however, do not represent the dorsal arms since they do not 

 connect with the head capsule. The usual place in adult insects for 

 the attachment of the anterior arms of the tentorium is at the lateral 

 ends of the fronto-clypeal suture; and for the dorsal arms of the 

 tentorium at some point near the antennal sockets. To a large ex- 

 tent this same relation holds true in immature stages. In the larvae 

 of the Cicindelidae the antennae are inserted so near the cephalic 

 margin of the frons that it leaves only a short distance between the 

 points of invagination of the anterior and the dorsal arms of the 

 tentorium and, as a result, the two have fused. The ventral arms 

 (vat, fig. 6) of the tentorium have also fused through the mesal fusion 

 of the epicranium. The invagination for the ventral arms of the 

 tentorium is on the meson at the caudal margin of the hjpostoma. 

 It extends entad a short distance, as a strongly chitinized structure, 

 and connects witli the anterior and dorsal arms. A thin plate-like 

 projection (fig. 6) extends caudad along the meson from the invagi- 

 nation for the ventral arms and, at the caudo-ventral part of the 

 head, is produced cephalad as a broad lamella-like structure. 



The ocelli, consisting of six pair, are on the vertex on the dorsal 

 and lateral aspects of the head. The diameter, distance apart and 

 comparative size of the two larger ocelli furnish excellent taxo- 

 nomic characters. To facilitate refering to the ocelli they have 

 been numbered, starting with the largest and numbering to the 

 smallest. Ocellus 1 {01, fig 8) is large, conical and quite prominent 

 and is on the dorso-caudal part of the head. Ocellus 2, {02, fig. 8) 

 is similar to ocellus 1 and is located cephalad on the dorso-lateral 

 part of the head. Ocellus 3 {03, figs. 5 and 8) is cephalo-ventrad 

 of ocellus 2, and ocellus Jf {04, figs. 5 and 8) is caudo-ventrad of 

 ocellus 3. The remaining two ocelli are quite small and incon- 

 spicuous and appear as transparent convex spots. Ocell^-s 5 {05, 

 fig. 5) is ventrad and slightly caudad of ocellus 2. Ocellus 6 {06, 

 fig. 8) is caudo-mesad of ocellus 2. 



Movahle parts of the head. — The antenna is inserted on the dorsal 

 aspect of the head laterad of each latero-clypeus. A slender, 

 chitinized bar extends from the vertex, between the mandible and 

 antenna, to the knob-like projection of the anterior arm of the 

 tentorium (fig. 5). The antenna (figs. 22 and 23) is four-segmented, 

 the second segment is the longest, the proximal and third segments 

 are subequal and the distal segment is the shortest. The number 



