274 THE WHITE S CATERPILLAR, 



4. THE POPLAR. 



AFFECTING THE LEAVES. 



In July, consuming all the leaf except its coarse veins, and reposing in a 

 cavity formed of leaves drawn together like a ball; large black cater- 

 pillars with white and yellow dots and stripes, and a hump on their 

 backs anteriorly and behind. 

 The "White-S, Clostera albosigma, new species, (plate 2, fig. 4.) 



Several different kinds of singular looking caterpillars, humped 

 upon their backs and otherwise closely related to each other, 

 occur upon the poplars and willows in Europe and this country. 

 Although these insects upon the two continents very much re- 

 semble each other, the remark made by Dr. Harris appears to be 

 correct, that they differ essentially in their caterpillar state, and 

 their moths also present certain characters, which, on close 

 comparison, will enable us to distinguish them. One of our 

 species, named the American Clostera by Dr. Harris, corresponds 

 in its marks with the anastomosis, and still more closely with 

 the reclusa of Europe ; and we come now to present another 

 similarly analagous to the curtula and anachoreta. 



The caterpillars attain their full size about the middle of July 

 and are then an inch and a quarter in length, black, dotted with 

 white above and with numerous wavy white lines on the sides, 

 where are two rows of yellow spots, and on the back are four 

 dull white stripes alternated with orange yellow on the middle 

 of each segment. On the top of the fourth or last thoracic seg- 

 ment is a conspicuous black hump prolonged into a teat-like 

 protuberance and a smaller hump upon the eleventh segment. 



The caterpillar has a cylindrical form, and is clothed with fine white hairs. 

 The white lines along each side form divers shaped rings and letter-like marks. 

 The stripes upon the back are interrupted upon the two humped segments, and 

 upon the middle of the two segments between the head and the anterior hump 

 is a slightly elevated point in each stripe, of a brighter orange color. The an- 

 terior hump is inclined backward, and is furnished with two long and numer- 

 ous short white hairs. The breathing pores form a row of broad oval black 

 dots along each side, each dot surrounded by a white ring. Above these is a 

 row of oblong yellow spots and below them another, each spot having a pimple 

 in its centre from which arises a hair, and the posterior spots of the lower row 

 having two of these pimples. On the third and fourth segments, the breathing 

 pores being wanting, the two yellow spots are confluent, forming a single 

 large spot with a pimple in its centre. The head is black and the Y-shaped 



