THE CANADIAN ENTOMOLOGIST. 223 



family is somewhat limited. It appears to be American, and to be 

 confined to the plains east of the rocky backbone of the continent lrom 

 north to south. In our fauna it seems to be a southern element. 

 Hubner calls this group Commiiniformes. Perhaps he intended thereby 

 to indicate a return to the more usual moth form, the fore wings tending 

 to become narrower, the secondaries subordinating, the abdomen lengthen- 

 ing. I have in my " Hawk Moths " alluded to the probability that the 

 Hawk Moths may be a further offshoot from the Lepidopterous stem in a 

 parallel direction with the Cei'atocampince. 



Sub-family Lachneince. 



In this group there is a return to the normal moth form with a 

 tendency to the lengthening of the abdomen noticeable in the caterpillars. 

 This lengthening of the abdomen and a certain weakness in structure 

 dependent upon this lengthening, seems to be indicative of lower rank in 

 insects generally and in the several suborders. The moths of the Lachneince 

 resemble preceding groups in the absence of ocelli and frenulum. The 

 hind wings are subordinate to the primaries, the colors mostly of shades 

 of brown and gray, with oblique transverse bands, more or less broken. 

 The palpi are more prominent than in the preceding groups, the tongue 

 remaining weak. The ornamentation of the long-bodied caterpillars consists 

 of tufts of hair. Our North American fauna is poor in species. We have 

 two genera derived from a former circumpolar fauna, also found in 

 Europe, Clisiocampa and Gastropacha. We have, then, two genera 

 which seem to me of South American extraction, Tolype and Art ace. The 

 species of Clisiocampa are very closely allied. They offer ground for 

 the correctness of the view which I have expressed that in North 

 America, species tend to vary, to throw off local, perhaps, what Walsh 

 called phytophagic varieties or species. The wide extent of country, with 

 its differing climate and flora, inhabited by Clisiocampa, has led to the 

 throwing off of specifically appearing forms, which may have hardened in 

 most cases into true species, separable in nearly all stages by external 

 characters. An instance is offered also by Datana, which I regard as an 

 offshoot from Phalera ; while there are only two species of Phalera, there 

 seem many closely allied species of Datana. The eggs are laid in a ring- 

 form on twigs, and the caterpillars of Clisiocampa are well-known as 

 enemies by the orchardist. 



