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Note. — Tetraglenes insignis, No. 75 of the foregoing list, is the 

 only insect I have seen possessing four distinct and widely separated 

 eyes. It is true that in Tessaromma, Tetraopes, Astathes, Phoea, Eus- 

 tathes, and several other genera of Cerambycites; and again in Chia- 

 sognathus (Tetraophthalma, Lesso?i), and other genera of Lucanites 

 and Gyrinites, each eye is apparently and perhaps really divided 

 into two : but in all these instances a cause for this division is to be 

 traced, and the normal integrity of the eye may always be imagined, 

 and in many instances is demonstrable, by the existence of a sutural 

 line connecting the separated portions. The normal form of eye in 

 Cerambycites is reniform, the insertion of the antenna occupying the 

 centre of its concave side ; and in proportion as the antenna; are dis- 

 tant from each other at the base, so will each be forced farther across 

 the superficies of the eye, until the connecting portion becomes a 

 mere line, and at length ceases to exist. In the Lucanites, &c., a por- 

 tion of the skull itself crosses the eye without much interfering with 

 its real figure, for the two portions when thus divided appear to form 

 parts of a single sphere. In Tetraglenes the case is different from 

 both these examples, each eye being apparently independent of the 

 other three, and there being no character or evidence by which we 

 can refer the two on either side to a common origin : indeed, were the 

 number of eyes in insects normally four instead of two, and were two 

 the exception instead of the rule, it would be most difficult to show, 

 by the intermediate structure in Tetraopes &c., the mode by which 

 each pair of eyes in Tetraglenes become merged in the single reniform 

 eye common to the Lamiidae. The eyes of Tetraglenes must be de- 

 scribed as four, two being circular, lateral, and very distant fi-om the 

 base of the antennoe, and two oblong and epicranial : all of them are 

 small. Very similar to Tetraglenes is an undescribed American ge- 

 nus, for which I propose the name of Spalacopsis : it may be readily 

 distinguished fi'om all other Lamiida?, by possessing the small circu- 

 lar lateral or cheek-eyes of Tetraglenes, and wanting the epicranial 

 eyes peculiar to that genus : the antenna? are approximate and 

 about as long as the body, and are porrected in parallel lines when 

 the insect is at rest : the first joint is longer than the head of the in- 

 sect, and is very obviously stouter than the rest ; the remaining joints 

 (after the second, which, as usual, is very short) gradually decrease in 

 length, and are somewhat pilose : the shape of the head is nearly co- 

 nical, the antennae occupying the apex of the cone and the mouth its 

 inferior basal angle : the insect is long and narrow, the head, protho- 



