PIERIXAE: THE GENUS CALLIUKYAS. 1045 



domed above, flattened beneath, scarcely coniprfsseil laterally, broadest at the summit 

 of the triangle; scarcely deeper below than above, the front nowhere appressed, tlie 

 median snture distinctly impressed on the snmmit; covered pretty uniformly and not 

 abunilautly with tubercules of two distinct sizes, the largest as large as the largest 

 ocelli and occupying principally the summit, each giving rise to a minute hair, whicli 

 excepting on the cheeks, is short and partially recumbent. Triangle less than half 

 as high as broad, reaching a little above the middle of tlie front. Antennae with the 

 tlrst joint moderately large, conical (?), the third al)outhalf as long again as broad, 

 narrowed at tlie tip and bearing a long and a short bristle, the former many times longer 

 than the joint. Ocelli six in nundier, four of tliem large and prominent, arranged in a 

 gentle curve, the convexity forward, at equal distances apart, except that the lowest 

 is removed a little downward ; the otlier two posterior ones are a little smaller, 

 arranged as in Eurymus. Labrum not large, shallowly and angularly emarginate in 

 front. Mandibles small. 



Body cylindrical, everywhere larger than the head, tapering a little forward from 

 the middle of the second thoracic segment, and bacl^ward on the last two abdominal 

 segments. Each segment divided into subequal parts, exactly as in Eurymns, but in 

 addition to the minute, hair-emitting tubercules of that genus, there are a smaller num- 

 ber of larger tubercles, one transverse row to each division of the body. Spiracles, 

 legs and prolegs much as in Eurymus, tlie front pair of legs considerably less than 

 half as long as the others. 



Chrysalis. Body cylindrical, tapering at both extremities, its form masked by 

 being l)ent upward in front, between thorax and abdomen, at an abrupt angle of 45°, 

 and by the immense extent of the wing cases, wliich form a protuberant, broad, 

 rounded and cuneiform-compressed lobe beneath. Though angulated and slightly 

 protuberant at the basal wing tubercle, the body is nearly of equal width from here to 

 the fourth abdominal segment; behind this the l)ody begins to taper, at first slowly, 

 afterwards rapidly, to the narrow-tipped creniaster; in front it tapers rapiilly and 

 regularly toward the base of the long and slenderly conical frontal tubercle. Viewed 

 laterally, the inequality in the size and form is excessive. A slight, concave curve 

 extends from the tip of the tubercle to the summit of the mesothorax, from whence 

 the line descends in a reverse sense to the end of the thorax, beyond which it is nor- 

 mal; beneath, a broad, J-shaped curve extends from the base of the frontal tubercle to 

 the tennination of the wings, at the end of the fourtli abdominal segment. There is 

 a distinct but not prominent mediodorsal carina over the whole extent of the body ; a 

 similar but more prominent lateral carina along the inner edge of the wings and just 

 above the spiracles. The eyes are not at all protuberant, the whole front of the body 

 scarcely convex. Tongue reaching somewhat beyond the antennae, but not reaching 

 the lower portion of the wing lobe. Preanal button scarcely raised above the surface, 

 showing a couple of minute, subdorsal, conical, pointed tubercles, and behind them a 

 pair of scarcely separated, slight, longitudinal, dorsal ridges. Creniaster with a 

 deep, cireular. hollowed pit on the ventral face, and a shallower one on the dorsal face, 

 the whole depressed, tapering, truncate, with swollen ridges, with the field of booklets 

 occupying the apical face and tlie apical portion of the inferior face, the booklets 

 much as in Eurymus. 



This group and Catopsilia, its Old AYorld representative, are peculiar to 

 the tropics, where they replace the genus Eurymus of the temperate re- 

 gions. Ciillidryas is twice a.s numerous as Catopsilia, and also spreads fur- 

 ther north by means of the single species here described, which has been 

 found even as far as the southernmost borders of New England. 



The butterflies are the largest of the subfamily, always exceeding two 

 inches in expanse. They are generally of a uniform greenish yellow. 



