590 MR. A. G. BUTLER ON THE SPHINGID2. 
Genus 9. CressontA, Grote and Robinson. 
Cressonia, Grote and Robinson, Proc. Ent. Soc. Phil. v. p. 186 (1865). 
1. CRrESSONIA JUGLANDIS. 
Sphinx juglandis, Smith and Abbot, Lep. Ins. Georg. vol. i. p. 57, pl. 29 (1797). 
Amorpha dentata juglandis, Hiibner, Samml. exot. Schmett. i. pl. 171. figs. 1-4 (1806-24). 
Polyptychus juglandis, Hiibner, Verz. bek. Schmett. p. 141. no. 1516 (1816). 
Smerinthus juglandis, Harris, Sill. Journ. vol. xxxvi. p. 292 (1839); Strecker, Lep. Rhop. & Het. 
pt. 7, pl. vii. figs. 12, 13 (1878). 
Cressonia juglandis, Grote and Robinson, Proc. Ent. Soc. Phil. vol. v. p. 161. no. 74 (1865). 
Sphinx instibilis, Martyn, Psyche, pl. xx. fig. 49, and pl. 21. fig. 53 (1797). 
3% North America, ¢ West Canada (Bush); East Florida (Doubleday). 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. rebinsonii, n. sp. 
2, CRESSONIA ROBINSONII. 
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. CRESSONIA PALLENS'. 
2, Smerinthus pallens, Strecker, Lep. Rhop. & Het. pt. 7, p. 54, pl. vii. fig. 14 (1873). 
Texas. 
In Mr. Strecker’s jocular strictures on the excellent subdivision of the Smerinthine 
proposed by Mr. Grote, he exhibits a weakness in admitting that S. juglandis and 8. 
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. Paontas, Hiibner (restricted) *. 
Paonias, Hiibner, Verz. bek. Schmett. p. 142 (1816). 
1. PaoNrAS EXCACATUS. 
Sphine excecatus, Smith and Abbot, Lep. Ins. Georg. i. p. 49, pl. 25 (1797). 
' Mz. Grote is confident that this is only a variety of C. juglandis. It looks quite distinct. 
* At once distinguished from Calasymbolus and T'riptogon by the form of the secondaries, which approach 
Laothoé in outline. 
