51 



species than the whole of Neuroptera, clearly disproves the exist- 

 ence of variety amongst their contents, equal to that amongst the 

 contents of Neuroptera. Yet the power, although weakened, is 

 by no means extinct ; for, amongst the central group, Phalaena, 

 we find the sub-classes, Papilio, Sphinx, Pyralis, Tinea, Noctua 

 and Geometra, most faithfully pourtrayed in Lasiocampa, ^Egeria, 

 Cilix, Lithosia, Apatela and Orgyia, and not merely the indivi- 

 dual genera which may happen to approach. As far as I can 

 discover, after this second series of types the faculty becomes 

 much weaker, and, after a third, ceases entirely. A decided 

 difference existing between the first and second series of types, 

 must on no account be lost sight of, because it so decidedly 

 proclaims the superiority of the first : in the first instance, the 

 whole character of the central type, Libellula, is completely 

 lost in each of the varying types ; whereas, in the second instance, 

 the characters of Phalaena are preserved most decidedly to the 

 remotest ramifications of the class, subject, however, to the 

 variations already pointed out. 



The natural order, Cossi, of which the larva and pupa have 

 been already described, contains but ten genera, even including 

 those whose claim to a place in the order is somewhat doubtful ; 

 and these ten are readily referable to six families. The genus, 

 Stygia, of New Holland, seems from Latreille's description, de- 

 cidedly to belong to this order. Speaking of Stygia Australis, he 

 says, " M. Villiers la considere comme intermediare entre les Sesies 

 et les Zygenes ; mats elle n^a point de trompe ; ses palpes sont 

 ceitx de Cossus ; ses antennes sont courtes, et nullement en fuse, 

 et plus analogues a celles de certains Bomhyx qu'a celles des 

 Sesies et des Zygenes* Now the fact, as M. Latreille supposes, 

 of having no antlia, argues most forcibly the impossibility of 

 uniting this genus either with Sphinx or Zygsena ; for the sub- 

 class Sphinx not only possesses the most elongate and con- 

 spicuous antlia of any sub-class, but retains this character to its 

 very circumference, and imparts it to approaching groups, whose 

 types will be found entirely aglossate : its similarity^ therefore 

 in shape to the Sesiae, which tribe is generally understood to 



* Regne Animal, torn. V. p. 395. 



