416 REVISION OF FAMILY SATURNIID^. 



The $ genitalia agree in this important particular : all the supra-anal 

 plates are strongly furcate at tip, with the possible exception of cal- 

 leto and sjjlendidus, the latter seeming to lack the plate entirely. 



Messrs. Packard aud Grote have made numerous genera out of the 

 American species, based on differences in wing shape and the course of 

 the veins; but after careful comparisons of hirge series of all the species 

 I have come to the conclusion that the separation is not maintainable, 

 and two genera only are recognized separated as follows: 



Abdomen untufted attacus. 



Abdomen tufted SAMIA. 



To the latter genus I refer cynthia only, which differs also in the 

 more extended secondaries from all the others of our species, but in no 

 further important particulars. 



The Limiean species atlas is taken as typical of the genus, and splen- 

 didus is its nearest i^orth American ally. A number of the species 

 described from Mexico and South America have been examined and 

 confirm the views expressed as to the generic identity' of our species. 

 It is somewhat remarkable that whereas our North American species 

 vary comparatively little and are rather sharply defined, the Mexican 

 and South American species vary exceedingly, and the limits of and 

 validity of many of the species described in the British Museum Cata- 

 logue are still very uncertain. 



SAMIA Hb. 



The only real distinguishing characters have been pointed out. The 

 structure of the head and thorax is shown at plate xiv, fig. 12, and need 

 not be more fully discussed, as the structure of the same parts in the 

 other species of the subfamily is alike. The primaries have ten veins 

 only, the 9th apparently not united to any other, but free from the 

 space between 8 and 10, as shown in the figure. In the specimens the 

 veins are contiguous, but in the figure they are enough separated to in- 

 dicate their course. 



The single species is — 



S. cynthia Dru., ii, pi. vi, f. 2 (Phala-na Attacus); Cram. Ex. i, 62, pi. 39, f. A {Pha- 

 ItBtia Attacus) ; Oliv. Euc. M6t.b., v, '30, 26 (Bombyx) ; Westw. Ed. Dru., ii, 12, 

 pi. 6, f. 2 (Saturnia) ; Hb. Verz., p. 156, 1629 (Samia) ; Wlk. Cat. B. M., v., 

 1220 (Attacus) ; Riley 4th Mo. Rept., 112 (Life Hist) ; Hulst. Biiln. BulL, i, 

 91 (food plant) ; Nostraud Bklu. Bull., ii, 75 (food plants). 



Wings dull luteo-fuscous, primaries with basal space brighter yellow- 

 ish and space beyond the outer transverse line bright yellow, densely 

 powdered with black atoms ; margin luteous gray. A strongly angu- 

 lated white band, shaded with lilac at base, outwardly shaded with 

 black, the outer angle touching the vitreous luuule. At the outer third 

 the wing is crossed by another, narrower white line, also tinged with 

 pale lilac, and with a broad shade of the same color outwardly. In- 

 wardly it is margined with black. As a whole the line is straight, out- 



