400 Mr. D. Sharp on: the Elaterid^e of New Zealand. 



base into a very large fleshy tubercle or false foot : the posi- 

 tion of this foot and the form of the ventral segment cause 

 the apical segment to be directed upwards in the two speci- 

 mens of this larva before me. 



This larva in its general characters agrees with those of the 

 Elateridae described by Perris in the " Insectes du Pin mari- 

 time" (Ann. Soc. Ent. France, 1854); but the dorsal plate 

 of the last ventral segment appears to be less divergent in its 

 structure from the other plates than is usual. 



Pupa about 26 m. ra. long, showing twelve dorsal seg- 

 ments besides the head, the first of which is quite of the form of 

 the prothorax of the perfect insect, but bears on each side of 

 the front a long slender tentacle ; the scutellum of mesothorax 

 very distinctly developed, the metanotum also largely deve- 

 loped. The dorsal plates of the hind body are distinctly 

 differentiated, the hind angles of the 3rd, 4th, 5th, and Gtli 

 segments being very prominent and hard ; the membrane 

 between the dorsal and ventral plates of the 6th segment is 

 elevated at its hind margin so as to form a kind of ear-like 

 cavity, which forms the anterior wall or protection of a very 

 deep depression at the outer side and base of the 7th segment, 

 this depression being limited behind by a strong elevation of 

 the dorsal plate of the 7th segment ; the terminal (9tli abdo- 

 minal) dorsal plate bears at its apex on each side two slender 

 spines, the upper one of which is short and simple, while the 

 lower one is very elongate, and bears one or two short spines. 

 On the under surface the trophi, antennse, legs, elytra, and 

 wings are very prominent. The hind body shows ten ven- 

 tral plates ; of these the seven basal ones correspond with the 

 dorsal plates, the 7th differing, however, considerably in form 

 from the others, it being much less transverse and greatly 

 rounded behind ; the 8th plate is not so largely developed as 

 the corresponding dorsal plate, while the 9th and lOtli plates 

 are small and protected by the projecting sides and apex of 

 the 9th dorsal plate. 



The peculiarities of this pupa seem to be the peculiar struc- 

 tural fossa on each side of the base of the 7th abdominal 

 segment, and the presence of an exposed supernumerary ventral 

 plate. In the perfect insect only five ventral segments are to 

 be seen : a comparison of the pupa with the perfect insect 

 renders it evident that the 7th ventral plate of the pupa is the 

 5th or apical segment of the perfect insect ; thus the diminution 

 in the number of ventral segments has occurred at both extre- 

 mities of the hind body — the first and second plates having 

 disappeared at the base, while the 8th, 9th, and 10th at the 

 extremity have become internal. 



