


32 BRITISH MOTHS 
FAMILY IV. 
TROCHILIIDA, Westrwoop. 
(Ageriide, Stephens, Newman, Westwood, olim.) 


This family consists of a number of very interesting insects, remarkable for their great resemblance to various 
Hymenoptera and Diptera, owing to the elongate form of the body and the nakedness of the wings, which are more 
or less transparent in most of the species. ‘The antennz are simple, fusiform or thickened towards the tips, and 
generally terminated by a small pencil of hairs. The ocelli are distinct, and the labial palpi have the second 
joint long and slender, and the last distinct and pointed at the tip. The spiral tongue varies in length, being 
not longer than the palpi in Sphecia. The legs are long, and the posterior are furnished with very long spurs. 
The abdomen generally terminates in a brush, capable of opening and closing at will; the veins of the wings 
are comparatively few in number. 
The larvee of these moths are fleshy grubs of a cylindrical form, with naked bodies, destitute of a caudal 
horn. They have six pectoral, eight ventral, and two anal feet. They live in the interior of the branches or 
roots of trees, of the debris of which they construct a cocoon, or at least a partial one. The chrysalis has the 
ventral segments armed with transverse rows of recurved points, whereby it is enabled to push itself through the 
cocoon, and half out of the hole in the stem which the larva had previously made, having had the instinct to turn 
in its burrow, so that the head of the pupa may be towards the orifice. The perfect insects differ in their habits, 
some being exceedingly active, flying about in the hottest sunshine or basking on the leaves, alternately expand- 
ing and shutting thew fan-tails; others, on the other hand (Sphecia), are extremely sluggish in the perfect 
state, resting on the trunks or leaves of the trees in which they have undergone their transformations, and flying 
heavily, a peculiarity analogous to that observed in the Smerinthi; in which, as in the genus in question, the 
tongue is almost rudimental. 
These insects are especially worthy of remark, from the difficulties connected with their natural situation 
amongst the Lepidopterous tribes. The ordinary location assigned to them, with the other species of Linnzan 
Sphinges, solely as it should seem from the structure of their antenne, and the analogical relations existing between 
them and the clear winged Sesiz, is disproved by their habits and transformations; in which latter respect they 
closely approach Cossus, among the Hepialide. Mr. Newman, indeed, on this account, introduced them into his 
“natural order Cossi,” (including Hepialus, &c.) ; but there are so many characters in the Imago state, in which 
these insects differ from all the rest of his Cossi, (amongst which the veining of the wings may especially be 
mentioned), that I consider such a step to be an unnatural attempt to bind nature to a preconceived numerical 
system. Indeed, if these moths are forced amongst the Cossi, it would be equally natural to introduce the New 
Holland Cryptophasiz, the internal feeding Noctuidae, or even many of the Tineide. Mr. Newman himself, in 
fact, admits, that “after all, so weak are the bonds of alliance, so far removed the only supposable approaches, 
that the family must be considered the most isolated that natural history affords ;’ and we consequently find in 
his ‘Grammar, that he has (without comment) separated them from the Cossi, into a distinct natural order. 
