I 



Sept. iSgg.] DVAR : LiFE-HlSTORY OF CoCHLIDION AVELLANA. 203 



arched. Lateral space broad, oblique, slightly concave, narrowing a 

 little toward the extremities. Subventral space very small, contracted. 

 Subdorsal ridge at first prominent, finally smooth, not elevated. Lat- 

 eral and subventral ridges moderately prominent, approximate, the 

 lateral at first tubercular, later smooth. Warts single haired ; in stage 

 I the subdorsal now bears two spines on joints 3 and 13, a single spine 

 with short branch about the middle on joints 4 to 12, leaning in alter- 

 nating directions ; later the warts are represented by tubercles bearing 

 two setge on subdorsal ridge and on the central thoracic wart, one seta 

 on lateral ridge ; in the last stage obliterated. Subventral seta^ rudi- 

 mentary, but persistent. Depressed areas moderately well developed, 

 rather small, rounded, slightly sunken, not very sharply defined, 

 smooth. The series (i) to (8) are present. Skin at first smooth, 

 later covered with papillose granules which become converted into 

 round granules with irregular divided crests or numerous thick spinules 

 and in the last stage with dense, round, clear granules of unequal size. 

 After the last molt the larva becomes very smooth but there is no dis- 

 tinct change in coloration, the ancestral yellowish green persisting. 

 The larva is marked like the leaves, adapted to escape observation. 



Affinities, Habits, etc. 

 This larva is allied to C. y-inversa Pack, as pointed out by Miss 

 Morton and myself (Journ. N. Y. Ent. Soc, III, 152), but it differs 

 in some interesting particulars that I did not suspect from the examina- 

 tion of my former material. It is in seVeral respects more generalized. 

 The color remains yellowish green nearly to the end, not becoming 

 suffused with white pigment as in y-inversa ; the outline of the lateral 

 ridge is slightly waved ; there is frequently a red border to the trans- 

 verse yellow line on joint 3 and the granules before the last stage 

 have irregular crests. In all these characters the larva departs from 

 y-inversa and approaches Heterogenea. There is no dorsal red patch, 

 as is characteristic in that genus, yet there is a distinct tendency to the 

 production of red color in the edge of the collar and the dark dots of 

 the subdorsal line. The condition of the granules is especially inter- 

 esting, for it explains the origin of the " fur " of Heterogenea, by the 

 splitting up of the apex of a papillose granule into short thick spines 

 which become borne on the crest of the granule and may easily be 

 imagined further modified into the " fur " structure by becoming slen- 

 derer and more attenuated. The larva belongs to the group of palse- 



