245] THE LARVAE OF THE COCCI NELLI DAE— GAGE 13 



reach the occipital foramen, they diverge laterad and form a ring around 

 the entire opening. 



The small bridge-like structure about one-half way between the lobes 

 of the corpotentorium and the occipital foramen is the laminitentorium 

 (Fig. 47, //). It is formed by the fusion of the ends of the pretentoria, 

 supratentoria, and metatentoria. 



The small pit on the ectal surface of the dorso-cephalic aspect of the 

 head where each pretentorium is invaginated is a pretentorina (Fig. 4, pt). 

 The point on the ectal surface of the head marking the place of invagi- 

 nation of each supratentorium is a supratentorina (Fig. 6, supt). It is not 

 present as a pit in coccinellid larvae. The metatentorina is the point of 

 invagination of each metatentoiium on the caudo-ventral aspect of the 

 head. The metatentorinae are not indicated by a pit or thickening. 



Movable Parts of the Head 



The form, structure, and arrangement of the movable parts of the head 

 of coccinellid larvae are readily homologized with the movable parts of 

 the head of generalized insects, such as Periplaneta or the larvae of Cory- 

 dalis or the adults of the Carabidae. The movable parts consist of the 

 antennae, mandibles, maxillae, and labium. 



The antennae of C. bivulnerus (Fig. 36) are about as long as wide, 

 slightly conical, and composed of three segments. The scape (Fig. 36, sc) 

 is cylindrical, wider than long, slightly chitinized, and bears a few fine setae. 

 The scape is attached to the heavily chitinized antennaria which bounds 

 the periphery of the antennal fossae (Fig. 36, ant) by a delicate membrane, 

 the antacoria (Fig. 36, ante). The pedicel or second segment (Fig. 36, pd) 

 is distinctly smaller than the scape, about as wide as long, and bears a dis- 

 tinct long seta on its mesal surface near the distal end. It also bears a 

 small number of fine setae. The flagellum, the small mound-like segment 

 on the distal end of the pedicel (Fig. 36, fl), usually appears to be a part of 

 the pedicel, but careful examination shows it to be distinctly separated 

 from it. The flagellum usually bears three peg-like setae which are prob- 

 ably tactile organs (Fig. 36, ts) and four small oval openings which are 

 probably sensoria (Fig. 36, se). 



The antennae of Epilachna (Fig. 35) are about three times as long as 

 wide; the greater part of the elongation is found in the pedicel. In this 

 segment the peg-like seta at the distal end is clearly a part of the pedicel 

 and does not appear as a part of the flagellum as in the other genera of the 

 family. In all of the genera of the tribe Coccinellini and in the genus 

 Microweisea the antennae are less than twice as long as wide and the 

 antacoriae are protuberant and might easily be mistaken for the first 

 antennal segment. The condition of the remaining parts is similar to that 

 of Chilocorus. In Hyperaspis the antacoria (Fig. 38, ante) is more pro- 



