14 Journal New York Entomological Society. [VoI. xxv. 



erably flattened against the surface to which it adheres by the viscos- 

 ity of the outer membrane. Newport ('57), speaking of Lampyris 

 noctiluca, states that at the moment of laying, the egg is covered with 

 a very adhesive sticky matter. Later the egg becomes firmer and 

 loses much of this stickiness. The laboratory period of incubation 

 was from about thirteen to fifteen days, a large batch of larvje hatch- 

 ing about July 24 in 1913. According to Newport, the egg state of 

 Lampyris noctiluca is about nineteen days. Vogel ('15) says that 

 oviposition of the same species usually occupies two or three days 

 and incubation twenty-seven to thirty, thirty-six, and even forty- 

 seven days, according to the temperature of the summer. Photinus 

 larvae which are ready to emerge have conspicuously black eyes and 

 brown mouth-parts. 



When freshly hatched the larva is about 2.35 mm. long, and 

 whitish, except for the blackish eyes and brown mouth-parts. Soon . 

 it becomes slaty gray with the head largely brownish. Its length, 

 exclusive of the retractile head, a few days later is 2.5 mm., and 

 the width at the second thoracic segment is 0.6 mm. The form is 

 oblong-elongate, broadest at the thorax and thence tapering gradually 

 toward the caudal extremity. The body is depressed, and rounded- 

 carinate mesially. There is also a subdorsal carina on the thorax, 

 which is less distinct on the abdomen and which marks the course of a 

 pale stripe. The head is about half as wide as the prothorax and 

 nearly or quite as long as the latter; the antennae are three-jointed, 

 the third joint is strongly chitinized and bears one globular and one 

 cylindrical sense-organ distally. The mandibles are arcuate, with a 

 finely pointed tip and a projecting preapical internal ridge. The 

 legs are slender and spinose, and under high magnification the body 

 appears roughly granulate. The single pair of prolegs is strongly 

 multi furcate, and the many filaments are thickly armed with rows of 

 ventral hooks, which occur also along the base of the furcation. The 

 larva has well-developed light-organs in the form of two small len- 

 ticular structures in the ventral portion of the eighth abdominal seg- 

 ment. These glow with a yellowish light. 



The duration of the first instar of Lampyris noctiluca is about 

 fifteen days according to Newport ('57). The first moult occurs 

 nineteen days after hatching. Under artificial conditions I found the 

 young Photinus larvae quite delicate, and I was able to carry but few 



