16 



Cincinnati Society of Natural History. 



Micro Heterocera, except those above placed in the first group, and 

 the few small Tineina yet to be discussed further on, viz., Cemiostoma, 

 Tischeria, Antispila, Aspidisca and Nepticula ; and we must also ex- 

 clude from it tliQ large silkworms, and among the Tineina. Plutella 

 oruciferarum. All the other Heterocera, the larval tropin of which I 

 have examined, comprising species of all of the families to be found in 

 this region, and of a host of genera, whatever may be their other 

 differences as to the form of the labrum, and size of the median notch, 

 or in any other respect, agree in having the labrum armed with twelve 

 spines, even when this forms almost the only bond of union between 

 them, vide figs. 60, 61 and 62. The next subgroup comprises, among 

 the Heterocera, Plutella cruciferarum (fig. 63) alone, which has the 

 twelve spines as in the last group, and in addition two very large spines 

 rising from the base of the labrum; and, strange to say, we do not meet 

 with this peculiarity again until we reach the Phopalocera, where the 

 skippers have the labrum of a very different form from Plutella, it is 

 true, but armed just as in Plutella (fig. 64, Eudamus tityrus). M} T 

 examinations of the larval trophi of Bhopalocera have been confined to 

 the skippers and Papalionidm. These latter (fig. 65) have the labrum 

 armed like Plutella and Eudamus, except that the two large spines are 

 placed much further forward than in those genera. P. cruciferarum is 

 an interesting species as to its classification. The characters of the 

 imago seem to me to locate it, as Mr. Stainton has done, immediately 

 above the Gelechidm ; yet here we find the structure of the labrum of 

 the larva separating it from all other Heterocera (except the silkworms, 

 of which see post), and allying it to the butterflies and large Attacidai. 

 The mandibles of the larva, too (fig. 44), are of somewhat unusual form, 

 sloping greatly at the upper basal angle, with two spines placed very 

 near the base (the figure 44 does not adequately represent the slope of 

 this part of the organ). The labrum is not only more strongly armed 

 than in other Heterocera, but has the teeth very large, and the an- 

 terior angles much produced, and the terminal processes of the 

 maxillae are of an unusual form (fig. 27).* 



*Its cocoon of open net-work is also remarkable and different from all other cocoons 

 that I have seen, though Chauliodus chserophylellus, and, perhaps, a few other European 

 species, are said to make such. Mr. Bates ("Naturalist on the Amazons," p. 413) de- 

 scribes and figures an open net-work cocoon, which, however, is suspended by a thread, 

 and which he attributes to a Timid; and Mr. Howard, while acting as assistant to Prof. 

 Comstock, in the Agricultural Department at Washington, showed me similar cocoons, and 

 a moth bred from them, which I recognized as the same insect that I had before received 

 from Texas, but which I think is hardly referable to the Tineina. It is a sordid, sooty 

 brown or blackish moth, with an expanse of wings of near an inch, and I think Mr. 

 Howard informed me that the larva came from Florida. 



