324 MODERN CLASSIFICATION OF INSECTS. 
in certain cases to decide to which of the two orders an insect may 
belong. Such is especially the case with Psyche, which Mr. Newman 
even places amongst the Neuroptera, and the Acentropus Garnonsii 
Curt. (Acentria nivosa Steph.), placed by Stephens in the order 
Neuroptera, and by Curtis in the Trichoptera, on the ground that the 
maxillary palpi are strongly developed, and the labial palpi absent. 
(Brit. Entomol. p. 497.) This character he has, however, set aside in 
treating of the genus Eriocephala, a curious group of minute (sup- 
posed*) moths (Tinea calthella Lenn. Se.), in which the labial palpi 
are minute, and the maxillary greatly elongated as in the Trichoptera, 
and in which the anterior tibiz are furnished with an inner spine, a 
character which is asserted to be possessed by no true Trichopterous 
insect. Acentropus, it is true, is destitute of any such spine, but then 
its four hind legs are also destitute of spurs, which would remove it 
both from the Trichoptera and Lepidoptera, and such, indeed, was 
the cause which induced Mr. Stephens to place it amongst the Neu- 
roptera ; but, notwithstanding the want of this character+, Acentropus 
appears to me to belong decidedly to the order Lepidoptera, possessing 
two characters peculiarly characteristic of the order which Mr. Curtis 
has overlooked, namely, a pair of large mesothoracic paraptera, or 
tegule, and the hook and bristle above described ; neither do I think 
Mr. Curtis justified in regarding the palpi of Acentropus as maxillary 
appendages, deeming them rather to be labial palpi. 
The classification of this order, as before observed, has hitherto 
been greatly neglected with respect to the true relations of the various 
groups founded upon a careful investigation of their, often recondite, 
characters. Linnzeus, in the earlier editions of the Systema Nature, 
adopted only two genera, Papilio and Phalzna. In the later editions, 
* The existence of a species possessing a character not according with that of the 
rest of the order is not sufficient ground for considering such character not to be 
characteristic of the order; and hence the possession by Eriocephala of maxillary 
palpi enormously developed, would neither be sufficient in itself to remove it from 
the order, nor to authorise us in not considering the comparatively superior length 
of the labial palpi over that of the maxillary, as characteristic of the order; but 
Eriocephala has other characters at least as strongly divaricating from the typical 
structure of the Lepidoptera, namely, the neuration of the wings, the formation of 
the labial palpi, and the general habit of the insect. 
+ If the existence of an internal spur on the anterior tibia were the real cha- 
racteristic to distinguish a Lepidopterous from a Trichopterous insect, a great 
number of species, belonging unquestionably to the former order, would require to 
be remoyed from it, especially amongst the diurnal species. 
