136 Journal New York Entomological Society. [Vol. vi 



the posterior one of anterior subventral fold and pxir on posterior fold. 

 On acquiring the last stage (VI) some of the lower spines become single. 



Stages IV to VII observed. Rather common on the hickory at 

 Bronx Park and Bedford Park, New York, in May. 



The $ of /. bipartitum Cress, closely resembles this species in color- 

 ation, but the head sculpturing and shape of clypeus seem different. 

 The 9 is unknown, and may turn out to be quite distinct from that of 

 /. caryicolum. 



Key to the Species of Isodyctium, 9*- 



1 . Head in part, at least orbits above pale 2 



Head black 5 



2. Black on bead confined narrowly to sutures 3 



Black on head covering most of vertex besides sutures 4 



3. Lobes of thorax yellow lined ; orbits narrowly yellowish floridense Dyar. 



Thorix and head uniformly red brown except for slight black marks. 



subgregarium Dyar. 

 4 Lobes of thorax yellow lined, orbits pale above, black before and behind. 



rileyi Cress. 



5. Upper half of pleura red or brown 6 



Pleura black 9 



6. Slender; ocellar basin narrowed, the vertical groove joining the transverse one be- 



tween upper ocelli 7 



More robust ; ocellar basin, triangular, the vertical and transverse grooves slightly 

 crossing 8 



7. Middle lobe of thorax brown ineequidens Nort. 



Thorax heavily black marked on all lobes murtfeldtiae Dyar. 



8. Thorax dark brown, the streaks on lobes obscure, brown ; abdomen brown at 



sides inf requens Dyar. 



Thorax brown, obscure streaks black ; abdomen yellow at the sides 9 



9. Rather slender, ocellar basin narrow, joining the stiaight transverse groove 



above cary icolum Dyar. 



Synopsis of the Larvae of the No^th American 

 Blennocampin^e so far as known. 

 The Blennocampinse have feet on joints 6-12 and 13, resting flatly 

 on the surface of the leaf; body thick and robust, as high as wide or 

 more so, except in leaf mining forms which are flattened and have de- 

 generate feet. 



The group is rather heterogeneous in appearance, but includes all 

 the leaf miners, all the spiny slugs and the smooth slugs that are thick 

 and robust. 



* bipartitum Cress, not included from lack of 9 specimen. 



