92 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



ending in two points, the innei- much larger, forming a long sharp spine. Penis a thick cylindrical 

 style, obtuse at the end. The armature difl'ers decidedly from tiiat of Anisota and Adelocephala 

 in the simple ilat suranal plate, the ^-spined claspers, and the thick obtuse penis. 



This genus, as already remarked by Grote. "'bears a remarkably close though superticial 

 resemblance to Smerinthus. and Boisduval afterwards stated that it has a slight resemblance to 

 certain varieties of Smerintluis popuJi in the shape of the fore wings, with their scalloped outer 

 edge." Also the tongue is unusually well developed, though Grote states that the oral struc- 

 ture is obsolete. This might by some be regarded as a case of mimicry, though the genus 

 probabl}' lived long anterior to a modern specialized sphingid. It diiiers from Adelocephala in 

 its larval characters, there being no dorsal spines on abdominal segments 1 to 7, as well as in the 

 genital armature; hence there seems no cause for uniting any of that genus with it. 



There is a good deal of discrepancy (Androrophy) between the two sexes, so much .so that 

 the female was referred ))y Grote to Adelocephala, and the male to his genus Psephopaectes. this 

 l)eing a remarkable case of male divergence from the more normal or primitive type," which 

 has been pi'eserved V)y the female. 



The head in front is much narrower than in Adelocephala, 

 and the clypeus is remarkably produced into a prominent knob- 

 like projection, which, so far as I know, is unique in the moths. 

 Larra — Stagr I. — Very similar to ^1. hicrilor, but body not 

 striped: prothoracic segment unarmed: eight long thoracic 

 horns like those of A. Vtcolot\ other spines as in liicolor, but 

 slightly more developed; caudal horn larger and higher, ending 

 in a thick swollen knob, which is square seen from in front, 

 with a bristle on each side. 



Last stage. — Body thick; it dift'ers from Adelocephala in the 

 Fiu.io.-Huad, denuded, of Si/sspAinxm-;;i«», thoracic spiucs being stout and verv short, while there are no 



mx, vestigial maxilla", male. . ., iii^^.i 



spines on the tirst to seventh abdominal segments; the caudal 

 horn is very short, not nmch higher than thick. The third thoracic and eighth abdominal 

 segments are swollen. 



Geographical distrthution. — This geniis ranges from the tropical zone or eastern coast of 

 Mexico (Jalapa) to Brazil, extending southward, according to Peters (in Schroder), to the La Plata, 

 and presumably northeastern Argentina. 



Food plant. — 'Muga vera." 



Ilistory of the genus. — The group is monotypic, there being but a single species, .S. niolma, 

 mentioned bj^ Hiibner, who placed it between the Sphinges and Endromis, quite remotelj' from 

 Eacles and Citheronia, the gap between being tilled by the Notodontida", Drepanulida?, certain 

 Saturniida;, and Aglia and Dirphia. 



SYSSPHIN-X ]M:OLI]Sr.A. iStoll). 



PI. XXXIII, fit:. 4. 

 Phaliena-Bombyx molinaSTOLh, Papillonn Exot., IV, p. 25, 221, Tah. .302, E. F. ( 9 ); Tab. 396, B. ( <J ). (I'Sl?) 



1782. 

 Phalsena molina Bepp, Papillons de Surinam, III, p. 2.59, PI. US, $ and 9 (Amsterdam, n. d. ). 

 Syssphinx molina HiJBHER, Verzeichniss Schmett., p. 143. 1818-1822. 

 Syssisphinx molina W.vlker, Cat. Lep. Het. Brit. Mus., VI, p. 1503, No. 1. 1855. 

 Fsepho2Mecles simuliitilw Grote, Trans. Amer. Ent. Soc, I, p. 6, PI. 1, fig. 1. $. 1867. 

 Adelocephala yrandis Grote, Trans. .•Vmer. Ent. SSoc, I, p. 8, PI. 1, fig. 7 9. 1867. 

 Verodere.f molina Boisdi-vai,, Annales Soc. Ent. Belgique, XV, p. 81. 1872. 

 Ceratocampa molina Buhmeister, Descr. phys. Rep. Argentine, V. Lep., Pt. 1, ji. 492, 1878; Atlas, p. 45, PI. xix, 



fig. 1, 1879. 

 Syssphinx molina Drvce, Biologfa Centr. Amer. Lep. Het., I, p. 172. .June, 1866. 

 Sym.yjhinx molina Kirby, Sj-n. Cat. Lep. Het., I, p. 741. 1892. 

 Syssphinx molina Dy.\r, Proc. Ent. Soc, Washington, VIII, p. 428. May 13, 1901. 



"See male preponderance (androrophy) in lepidopterous insects, bv A. S. Pacliard. Science, XVII, p. 2.50, 

 Feb. 13, 1903. 



