43 



or imago. The larva from which a collector of liCpidoptera 

 could expect to obtain such an imago would be unicolourous, 

 stouter in the middle, elevated in the penultimate segment, and 

 more attenuated towards the head.* Pygaera appears doubtful 

 at first, but when observed quite at rest, and in a perfectly 

 natural position, elevates the head and tail, though in a much 

 less degree than the ty^jical genus. Mr. Curtis's genus Noto- 

 donta contains several good species, which may be considered as 

 typing the order, as Ziczac, Tremula, and Dictseoides. The 

 first species, Trepida (the Peridea serrata of Mr. Stephens,) seems 

 more nearly related to Endromis. Both these may, however, 

 probably belong to the order Notodontae, and be situate near the 

 approach to the central order Phalaenas. Petasia cassinea and 

 Episema caeruleocephala appear to be genuine Noctuae, and very 

 near Chareas graminis, and Rusina ferruginea, as far as my very 

 imperfect knowledge of these four species will allow me to 

 judge. Clostera is another departure from the type ; but this 

 may be accounted for, in some degree, by its close proximity to 

 Hepialus, from which genus it borrows its remarkably short 

 antennae, and other peculiarities. It seems a strange perversion 

 of judgment to place Platypteryx at the end of or among the 

 Geometrae ; but Linnaeus did so, and that is enough. Hubner, 

 Haworth, and a few others, positively ventured, in this glaring 

 instance, to refer this genus to the Bombyces ; but their ideas 

 were thought to be wrong, and their judgment was, nem. con. 

 reversed. I have elsewhere expressed a wish that my readers 

 should convince themselves, and the frequent occurrence of the 

 larvae of Platypteryx and Cerura would afford any naturalist 

 abundant opportunity of ascertaining, that they can be referred 

 to but one order. The approach of Platypteryx and Cilix to 

 the Pyralides, in assuming so much of their characters, is very 

 interesting, and is a most striking departure from the typical 

 form. These genera also approach the Lithosiae, but not so 

 nearly as some exotics. 



Natural Order — Lithosice. The difference between Lithosiae 



* As the larva so decidedly forbids the introduction of this insect amon^ 

 the Notodontae, and places it among the Noctua?, it probably in some degree 

 approaches Geometra pennaria in the adjoining sub-class, 



D 2 



