Benj. D. Walsh on Prof. Dana. 121 



PlatyphyUum, with the elytra of those Coleoptera where, instead of being 

 corneous as usual, they are coriaceous, e. g. Lytta, Phot Inns or Tele- 

 phorus, we shall always find in the former, with the single exception of 

 /•'< rficula, a regular system of numerous, large, branching, reticulate 

 wing-veins, plainly visible to the naked eye on both surfaces, as in 

 other Orthoptera ; while in the latter there is no such system, but 

 only, as in other Coleoptera, two or three simple longitudinal veins at 

 the most, which are often traceable on the lower surface alone. The 

 reason is obvious. Where, as in almost all Orthoptera. the front wing 

 is a flying organ, the structure of the wing-veins is elaborated, so that 

 besides their normal function as veins they perform the additional 

 function of the bones in the wing of a Bat. In Forficula on the contrary 

 | F. auricularia of Europe), where the representatives of the anterior 

 wings are as truly elytra or mere wing-cases as they are in Coleoptera, 

 they are of a uniform, semi-transparent, coriaceous substance with two 

 or three straight, simple veins only, as in Coleoptera; which no doubt 

 was one reason why Linnaeus referred this genus to Coleoptera. Even 

 in Ileteroptera. we find in the coriaceous basal part of the wing a 

 similar system of branching veins, connecting with those in the mem- 

 branous terminal part; which indicates that here also the front wings, 

 or '*' hem elytra" as they are called, are used more or less in flight as 

 well as in Orthoptera, though from the generally small size of these 

 insects I do not know that the fact has been proved by actual observa- 

 tion. Certainly, from the analogy of Forficula, we may infer that 

 they are so used. For in Forficula that portion of the hind wing, 

 which when the wings are folded up is unprotected by the elytrum, 

 is coriaceous; just as in Heteroptera that portion of the front wing, 

 which when the wings are folded up is unprotected by the overlapping 

 portion of the other front wing, is coriaceous. Yet Forficula, as it 

 is known to fly vigorously by night, must necessarily fly with its par- 

 tially coriaceous hind wiugs ; for its elytra are altogther too small for 

 the purposes of flight. Consequently we may infer, that Ileteroptera 

 also use their partially coriaceous front wings more or less in flight. 



PROCEEDINGS ENT. SOC. Mill. AD. JFNK, 1SG6. 



