Ægocerides, &c. That of Crepuscular is adapted more or less to some sphinges, but by no means to the Zygenides, which fly only in the heat of the sun. Finally, the term Nocturnal is not more properly applicable to all the species, since many belonging to this section appear only during the day. In order to avoid these improper denominations, we have substituted for the word Diurnal, that of Rhopaloceres, proposed by M. Dumeril. Being unable to perceive limits between the Crepuscular and Nocturnal divisions of Latreille, we have united those two great sections under the name of Heteroceres. In our method, therefore, the lepidoptera are divided into two grand legions, Rhopaloceres and Heteroceres[1]."
Dr. Boisduval then proceeds to explain that the first of these divisions is characterised by antennæ thickening to a club at the extremity; and the second, by having these organs variously shaped; this indeed is implied by the words themselves. The first division is subdivided into three sections, according to the manner in which the caterpillars transform themselves into chrysalides. Such as undergo this change by attaching themselves by the tail and a band round the middle, form the first division, named Succincti; such as are suspended by the tail only, the second, Penduli; while those which form a cocoon by rolling leaves together, compose the third division, termed Involuti.
- ↑ Species général des Lepidoptères, p. 158.