1923 12 ] CLARK — THIRTY-THREE NEW SPHINGIDAE 55 



Clark. A gift from my friend, Rev. A. Miles Moss, who reared them under 

 great difficulties. He has specimens in his collection. 



The remarkable larva of this species was described by Rev. 

 A. Miles Moss (Novitates Zoologicae, XXVII, p. 378) and at 

 that time was considered by him to be a subspecies of I. swain- 

 soni Felder. It is quite clear, however, that this is not the 

 case. Mr. Moss wrote me fully in September, 1922, and I quote 

 in full all that he says, because he has done such distinguished 

 work in the Sphingidae that his observations are of deep 

 interest. 



"I am now convinced that though most closely allied to 

 swainsoni on the one side, and leachi on the other, and not far 

 from excelsior as a third ally, it is a good species, and really 

 specifically distinct from all three. Note these highly important 

 differences, jotted down as they occur to my mind, and very 

 fresh from some recent comparisons. 



"1. The belted character and color of the larva of zebra is 

 constant throughout, from egg to pupa, only that the head, 

 plate, claspers and anus become increasingly bright orange 

 vermilion, the black becomes more intensely velvety, and the 

 white more purely white if possible (no trace of greenish or 

 lemon-yellow anywhere, and no ochre as in the head and anus 

 of swainsoni). The tail, from being considerably longer than 

 the body in instar 2, becomes normal in length, as in leachi, in 

 final instar ; always dead black in final instar, very frail, easily 

 broken, and eaten off by his fellow creatures. After moulting 

 they all love to devour their old skins. 



"2. Pure white belts in the larva of zebra reach right down 

 to the red claspers. This is never so in either leachi or excelsior, 

 but is so also in swainsoni. But note, these white belts in zebra 

 are narrow and in middle of segment, thus giving twice as much 

 black. The reverse holds good, I think, in swainsoni, and I 

 never saw any red about the larva, so remarkable and striking 

 a feature with zebra, shared by one form of excelsior to the last, 

 and by leachi, but less flaming red, only to end of 4th instar, 

 when a complete change of body pattern invariably takes place. 



