56 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION 



niinute pimple is also seen forward of the upper end of each breathing pore, below^ 

 -which all the under side of the worm is greenish white. The breathing pores are oval 

 and light yellow, with a rusty brown oval spot in their center and a dark purple ring 

 around their outer edge. Below them the skin bulges out, forming a longitudinal 

 ridge, or rather two parallel ridges divided by a deep intervening furrow. Upon the 

 upper one of these ridgea near the middle of each ring is a round cherry-red spot in 

 which are two small pimples, and on the lower ridge is a single one, placed farther 

 back, whilst four others equally minute may be seen farther down and around the 

 anterior base of the prolegs. The second and third rings are shorter, each with four- 

 teen pimples of different sizes, the larger ones forming a single transverse row. The 

 first ring or neck is polished and of a dark tawny brown color on its upper side, with 

 a white line in its middle disappearing anteriorly in a black two-lobed cloud. The 

 head is but half as broad as the body, and is of a shining black color, tinged more or 

 less with chestnut brown in its middle, with scattered punctures from which arise fine 

 hairs. The antennte are chestnut brown, conical and three-jointed, the last joint 

 minute, with a bristle beside it given out from the apex of the second joint. The 

 palpi are similar, with two small processes from the summit of their second joint, 

 the outer one of which ends in a minute fourth joint. Of the eight pairs of legs, the 

 three anterior are conical and end in a single chestnut-colored claw. The others are 

 short, thick, and retractile, with their soles surrounded by a blackish fringe-like ring 

 composed of a multitude of minute hooks, the last pair, however, having these hooks 

 only around the anterior and outer half of their soles. Placed in a glass or tin vessel, 

 this worm is perfectly helpless, being unable to cling with these hooks to a hard 

 smooth surface. 



With the last change of its skin it loses its bright-red color and is then white, 

 tinged with green at the sutures, and with a pale-green stripe along the middle of its 

 back, which disappears at the sutures. The pimples are of a pale tawny yellow color 

 with black centers. The head is light tawny yellow varied in its middle with green- 

 ish white, its anterior edge blackish and the jaws deep black.* 



As the moth into which this worm changes possesses no jaws or other implements 

 by which it is possible for it to perforate the wood, it is necessary for the worm to pre- 

 pare a way for its future escape from the tree ; and the provisions which it makes for 

 this end are truly interesting, indicating that the worm has a clear perception of what 

 its future condition and requirements will be, both in its pupa and its perfect state. 

 This is the more surprising when we recur to the fact that since its infancy this crea- 

 ture has been lying deeply bedded in the interior of the tree, the only act of its life 

 having been to crawl lazily around in its cell and gnaw the wood there when impelled 

 by hunger. How does it now come to do anything different from what it has been 

 doing for months and years before ? But, having got its growth and the time draw- 

 ing near to have it change into a pupa or chrysalis, we see it engaging in anew work. 

 It now bores a passage from the upper end of its cell outward through the wood and 

 bark till only a thin scale of the brittle dead outer bark remains. It is usually at the 

 bottom of one of the large cracks or furrows in the bark that this passage ends, 



* Received full grown larvse from F. G. Mygatt, Richmond, 111., February 26, 1868, 

 found boring in a large black-oak tree, forming their cocoons soon after the receipt. 

 The male larvae have generally broken bands of reddish brown across the middle of 

 each segment. The female larvae are perfectly fulvous or of the color of ordinary 

 yellow butter; subcylindrical; thoracic segments broadest, tapering thence to 

 anus. Segment 1 flatter than the rest; head polished brown and fulvous; pilifer- 

 0U3 spots variable in size, being more distinct when young, and often connected by 

 transverse bands of brown; stigmata brown, large, and distinct; feet and legs 

 6ame as venter, the former with brown extremities, the latter fringed with brown ; 

 anal segment more glaucous than the rest. Others were received from J. M. Shaffer, 

 January, 1870, found boring in black locust, and were exactly like the oak-feeding 

 specimens. (Riley's unpublished notes.) 



1 



