590 ME. A. G. BITTLEE ON THE SPHINGIIXE. 



Genus 9. Cressonia, Grote and Robinson. 

 Cressonia, Grote and Robinson, Proc. Ent. Soc. Phil. v. p. 186 (1865). 



1 I 1. Ceessonia juglandis^ 



Sphinx juglandis, Smith and Abbot, Lep. Ins. Georg. vol. i. p. 57, pi. 29 (1797). 



Amorpha dentata juglandis , Hiibner, Samml. exot. Schmett. i. pi. 171. figs. 1-4 (1806-24). 



Polyptychus juglandis, Hiibner, Verz. bek. Schmett. p. 141. no. 1516 (1816). 



Smeri?ithus juglandis, Harris, Sill. Journ. vol. xxxvi. p. 292 (1839) ; Strecker, Lep. Rhop. & Het. 



pt. 7, pi. vii. figs. 12, 13 (1873). 

 Cressonia juglandis, Grote and Robinson, Proc. Ent. Soc. Phil. vol. v. p. 161. no. 74 (1865). 

 Sjjhinx instibilis, Martyn, Psyche, pi. xs. fig. 49, and pi. 21. fig. 53 (1797). 



<? $ North America, <S West Canada (Bush) ; East Florida (Boableday). B.M. 



We have a pair of what seems to be a second species ; it is of a greyer tint and 

 half as large again, the transverse lines wider apart, and the primaries with central 

 band not darkened on the inner margin. I propose to call it C. robinsonii, n. sp. 



2. Ceessonia eobinsonii. 



Cressonia robinsonii, Butler, supra. 



New York. Type, B.M. 



It is quite possible that the above may be a large form of C. juglandis ; but it differs 

 noticeably from our six examples of that species. 



3. Ceessonia pallens 1 . 



2, Smerinthus pallens, Strecker, Lep. Rhop. & Het. pt. 7, p. 54, pi. vii. fig. 14 (1873). 



Texas. 



In Mr. Strecker's jocular strictures on the excellent subdivision of the SmerintMnce 

 proposed by Mr. Grote, he exhibits a weakness in admitting that S. juglandis and S. 

 pallens might be placed in one genus, provided that uniformity of shape in the wings 

 were taken as the basis thereof. I find that dissimilarity in the outline of the wings 

 is almost always accompanied by modification of the discocellular nervelets, which would 

 be sufficient in the eyes of any Lepidopterist to warrant generic separation. 



Genus 10. Paonias, Hiibner (restricted) 2 . 

 Paonias, Hiibner, Yerz. bek. Schmett. p. 142 (1816). 



1. Paonias excjec atus. 



Sphinx exccecatus, Smith and Abbot, Lep. Ins. Georg. i. p. 49, pi. 25 (1797). 



' Mr. Grote is confident that this is only a variety of C. juglandis. It looks quite distinct. 

 - At once distinguished from Calasymbolus and Triptogon by the form of the secondaries, which approach 

 LaolJwe in outline. 



