48 



In coloration this larva is somewhat suggestive of the common cab- 

 bage looper, Plusia brassicce, but the form is entirely different, being 

 much more slender, and although the species is a semi-looper, like 

 Plusia, it is not at all likely to be mistaken for it. The colors are 

 somewhat more constant in the several stages. 



The penultimate stage. — The larva is green and white striped and is 

 in its most characteristic colors when in the penultimate stage, as it 

 loses its striation to a great extent when fully matured. The general 

 color is clear, translucent green, a shade or two lighter than the bean 

 or other leguminous leaves upon which it feeds. It is about ten times 

 as long as wide and segmentation is well marked. The body is widest 

 about the middle, tapering gradually toward each end, the last seg- 

 ments being narrowest. The head is of nearly the same color as the 

 remainder of the body, a trifle lighter and less translucent. The entire 

 surface of the body is sparsely covered with long, slender, and dark 

 brown hairs. The piliferous warts project above the surface, but 

 otherwise are not noticeable, being only a very little lighter in color 

 than the body. The thoracic legs are nearly the same color as the 

 head. There are only three abdominal prolegs. The anal prolegsare 

 long and project well beyond the last segment. There are six white 

 stripes on the bod}^ which alternate with the general green. The green 

 dorsal line is a little darker than the general color of the bod} T . There 

 is a rather wide white stripe each side, a latero-dorsal narrow white 

 stripe, and a broader irregular lateral stripe. The prothoracic folds 

 are strongly pronounced, particular ly in the region of the legs; abdom- 

 inal folds also pronounced. Length in this stage, 20-24 mm : width, 

 2.4-2. 6 mm . ' 



Last larval stage. — After the final molt the larva usualty loses to a 

 great extent its striated appearance and becomes nearly uniform paler 

 green in color as well as stouter. The head is sometimes somewhat 

 yellowish, as is also the first thoracic segment. The ocelli are twelve 

 in number, arranged at the sides of the head in three pairs, as shown 

 in the figure at g. 



In alcohol the larva loses its color, being apt to be turned black 

 unless first boiled in water, when the color becomes milk white. Length 

 at maturity, 25-29 mm ; width, 2.8-3.0 mra . 



The penultimate stage is figured because, as previously remarked, 

 more characteristic of the species than the final stage before pupation. 



THE PUPA AND COCOON. 



The pupa. — The pupa is dark brown and presents rather good char- 

 acters for description, but as this stage has previously been very fully 

 characterized by Professor Comstock, in the report of this Depart- 

 ment for 1879, his description is transcribed: 



Rather stout, d&rk mahogany-brown. Wing sheaths and crural sheaths closely 

 soloV'vd; the t'ornier obtusely rounded and extending to the end of the fifth abdom- 



