146 KANSAS UNIVERSITY QUARTERLY. 



f^t^ The next subclass is represented by 

 Papilio euryinedon (fig. V), in which the 

 lobes are entirely wanting, the entire 

 dorsal surface of the prothorax except 

 the median scutellum being of a membranous character. The pro- 

 thorax is broader than that of Colias, and the scutellum larger, of 

 more complicated form and very prominent. The prothorax is deeply 

 cleft in front by the narrow portion of the scutellum at its juncture 

 with the chitenized collar; just back of the cleft this narrow 

 neck widens abruptly into the broad, deeply fork-shaped scutellum, 

 which is raised prominently above the rest of the prothorax. 



The sternum differs from that of Co/ias in having a second narrower 

 band lying just anterior to the first. The two are coalesced at the 

 junction with the dorsal band, the point being marked by a small 

 tumid lobe. 



The last subclass is represented by 

 Fieris rapu\ fig. \l. The prothorax is 

 not as broad as in the preceding. There are 

 no lobes, but the spaces occupied by the 

 lobes in other forms is here represented by two triangular concave 

 surfaces, unchitenized and yellowish white in color, and showing the 

 insertion of the scales. The lateral extremities, which project ceph- 

 alad slightly, are apparently partially chitenized and are much darker 

 in color. The median cleft between these two surfaces is broader 

 than in the others described and the broad triangular scutellum joins 

 smoothly with the chitenized band in front. The general shape of 

 the prothorax is that of Colias civronia with the exception of the 

 lobes, the membrane rolling back slightly along the front in the same 

 manner. The articulating band just beneath the anterior margin of 

 the mesothorax is rather broader than in the others described and 

 more noticeable. 



Lycceuidic, fig. VII. In this group the 

 prothorax is very small, there are no 

 lobes, only the narrow concave surfaces, 

 very much as in Fieris. These surfaces 

 are so placed that the anterior margin is much lower than the pos- 

 terior, thus throwing the flattened surfaces so that they lie in an almost 

 vertical position. The scutellum is very narrow but its slender lateral 

 extremities extend almost across the dorsal surface of the prothorax. 

 The narrowed portion of the scutellum and the sclerites articulating 

 with the mesothorax are entirely concealed. The prothorax is closely 

 set with broad scales. The sternum and episternum are coalesced, 



