28 



Titynis, as usually found in the Northern and Eastern parts of North 

 America, there is along the outer margins of both wings, beneath, a 

 broad shade of pruinose atoms extending on the primaries from the 

 apex nearly to the inner angle, and on the secondaries from the costal 

 edge two-thirds of the way to anal lobe. This character is almost 

 wanting in Zestos, but is in all specimens under my notice, faintly in- 

 dicated by a reflection which is undoubtedly caused by a slight sprink- 

 ling of the same atoms observed in Tityriis: so that ' ' the more uniform 

 color' ' in Zestos is only caused by a partial absence of these atoms and 

 not by the entire absence of any positive character constant to Tityrus. 

 The uselessness of this character is all the more manifest when Zestos 

 is compared with certain specimens of Tityrus from Arizona, Tennes- 

 see and Philadelphia, in my possession. Two of these, from Arizona 

 and already alluded to, have all the characters of Zestos mentioned by 

 Mr. Worthington, except the absence of the silvery spot on under side 

 of secondaries. Those from Tennessee (two) and from Philadelphia 

 (five) were all bred on Locust {Robmia), and the Philadelphia speci- 

 mens were starved so severely that they were the only survivors of 

 thirteen larvae. These nine aberrant specimens of Tityrus approach 

 much nearer to Zestos in their uniform coloring beneath than to typical 

 Tityrus, from which, as already observed, they also differ in the lack 

 of confluence, and the opaqueness of the yellow spots on the primaries. 

 Together with these characteristics of Zestos, these and other speci- 

 mens of Tityrus have also ' ' the purplish cast' ' mentioned as another 

 peculiarity of the former. This, moreover, is frequently observed in 

 freshly-bred specimens of Tityriis, especially those from the Southern 

 States, and in one specimen before me is also quite decided on the 

 apex of the primaries above. 



The " entire absence of the large silver spot so prominent in its ally" 

 ( Tityrus) is now the only character left us whereby we may with cer- 

 tainty distinguish Zestos from Tityrus, and it remains to be seen whether 

 even this seemingly inarked peculiarity is sufficient to warrant their 

 separation specifically. 



In the summer of 1882 I had, among other species of Hesperid larvae, 

 about fifty larvae of Tityrus feeding on Robinia. Through carelessness 

 thirteen of these, which were in a compartment of my breeding-cage 

 alone, were overlooked, and no food was furnished them for three days. 

 When discovered two of them had succumbed, several others bid fair to 

 follow their example, and all were much shriveled and reduced in size. 

 This seemed to afford such an excellent opportunity for the observance of 

 the effects of starvation on larvae, that I continued this neglectful treat- 

 ment as rigorously as possible until all but seven were dead. Of these 

 seven, one had not sufficient strength to spin its pupa-case, and another 

 died when almost entirely transformed to the pupa state. Of the five 

 remaining ones three emerged on August 4th, another on the 6th, and 



