2 Rev. II. S. Gorliam's materials for a 



which I now proceed to give, will always separate them. 

 Lacordaire thus defines these differences : — 



Intermediate coxse separated by an interval — 



I. — Lycidce. 

 Intermediate coxa close to each other — 



Antennae inserted close together . . II. — LamjjyrxdcB. 



Antennae separated . . . . . . III. — Telephoridce. 



On this I will merely remark that as we study the 

 general structure of Photnris, it will be found to recede 

 further from the Telephorides, e. g., in the development of 

 the eyes, correlated with that of the production of light 

 in the female, and in the structure of the abdomen, of 

 which more hereafter. 



I now go on to speak of the generic classification of 

 these insects. If Motschulsky used the number of appa- 

 rent light-giving segments in the abdomen, to the neglect 

 of more important modifications in its structure, yet on a 

 review of the more natural arrangement to which Lacor- 

 daire reduced his genera, or rather restored the family, 

 we shall see a distinct relation between the development 

 of the phosphorescent power, and many, if not all, the 

 other modifications. Thus in the first section in which 

 both males and females are equally provided with wings, 

 and in which those remarkably beautiful flabellate antennae 

 are found, the light-giving parts are confined to one or 

 two small points, and the eyes, especially those of the 

 males, are not of extraordinary size. While in those 

 genera which form the latter half of this section (Lucido- 

 tides), and are contained in the two following {Lampyrides, 

 Liiciolides), and in which the phosphorescence reaches its 

 greatest development, the antennae are reduced to simple 

 filiform, often very short organs, and the eyes of the males 

 are so enlarged as to resemble small seeds. In short, if 

 I see the head of a Lampyrid, I can predict the greater 

 or less phosphorescence of the ventral portion. 



And beyond this I have found that the best generic 

 characters lie in the structure of the last or last but one 

 abdominal plates ; these are cut out or lobed in a manner 

 varying in each genus I have yet examined, sometimes 

 alike in each sex, at others differently. These portions 

 are apt to shrivel in such soft-bodied insects, enhancing 

 the difficulty of examination in old specimens. I there- 

 fore must ask some indulgence for the merely partial 

 description of these parts, and for the mere attempt at 

 drawings of them which I have to offer. 



