Jan., '04] ENTOMOLOGICAL NEWS. 5 



In their earh' stages (i and 2) the two genera are much 

 alike, especially R. orizaba and A. atlas, but the freshly 

 hatched larva of Attacus differs in having much longer tuber- 

 cles. In the second stages the differences are still more pro- 

 nounced. Now in the third stage, or with the second molt, as 

 is well known, there is a great acceleration of characters, and 

 the larva suddenly assumes the markings and armature of the 

 last stages, with of course some important differences. From 

 this time on the two genera, Asiatic and American, follow 

 widely divergent paths. In the neogseic genus (Rothschildia) 

 the tubercles tend to become reduced, becoming in the fully 

 fed larva small and button-like, until in R. betis they have, 

 judging from Burmeister's figure, become wholly atrophied. 



In Attacus, however^ after the second molt the tubercles be- 

 come long and finger-shaped, while the spines have disap- 

 peared. This specialization is maintained through all the suc- 

 ceeding stages with the result that we have a very diiferent 

 larva from that of Rothschildia , the tubercles of the dorsum 

 more especially being long, digitiform and somewhat pointed ; 

 it has also retained the long tubercle in front of each protho- 

 racic spiracle, of which only the merest vestiges are present 

 in Rothschildia . 



The genus Attacus is evidently the end or terminal twig of 

 a series of Attacine forms, as shown both in its larval and 

 adult characters. The great size of the species is a feature of 

 its specialization, just as the big mammals, such as the ele- 

 phant, hippopotamus, and whales, are the result of extreme 

 specialization due to their habits and surroundings. 



Of the genus Attacus there are four species, inhabiting 

 southeastern Asia, or the oriental region of arctogaea. Of these 

 A. atlas appears to be probably the stem form, and occurs in 

 Southern China (Macao and India). A. crameri, apparently 

 the most extreme and recent form, inhabits Aniboina, A. 

 ccesar Mindanao, A. atlas var. lorquiuii also the Philippines, 

 and^. imperator, Bohot, one of the Philippine Islands ; all these 

 forms being local varieties resulting from local variation and 

 isolation. The magnificent and very rare form, Coscinocera , 

 Queensland TTring Museum), Northern New Guinea, New 



