105] LEPIDOPTEROUS LARVAE — FR ACKER 105 



Genera of Liparidae : 



a. Body bearing tufted setae but no long pencils or dense verricules. 

 b. Abdominal segments bearing a single large verruca, eta, below 

 spiracle, with a very small one, mu, behind it ; verruca rho fused 

 with kappa dorso-caudad of the spiracle ; verruca alpha on ab- 

 domen distinct, tho small. Porthetria 

 bb. Abdominal segments bearing two large verrucae below spiracle, 

 mu directly below eta ; kappa, when present, distinct, behind 

 spiracle ; verruca alpha fused with beta, 

 cc. Verruca kappa present and distinct, tho small; body bearing 

 some very feathery setae. Gynacphora 

 cc. Verruca kappa absent or indistinct ; setae echinulate but not 

 feathery. Euproctis 

 aa. Body bearing a pair of long pencils of setae on prothorax and a 

 mesal pencil on segment 8. 

 b. First four abdominal segments bearing dense dorsal verricules 

 very different from verrucae of other segments. 

 c. Clavate-plumed setae present on all or nearly all segments. 



(In part) Olene 



cc. Clavate-plumed setae present only in the tufts of the prothorax 



and eighth abdominal segment and sometimes on the second 



abdominal segment. Hemerocampa 



Notolophus 



bb. First four abdominal segments bearing verrucae similar to those 



of other segments. (In part) Olene 



Porthetria includes a single species, the Gipsy moth, P. dispar. 



Euproctis chrysorrhea is the Brown tail moth and is the only spe- 

 cies of this European genus as yet introduced into America. 



The characters given for Gynaephora in the synopsis refer to G. 

 rossii, the larva of which differs greatly from G. groenlandica. The 

 latter species occurs only in the Arctics. 



Olene achatina differs from other members of the second group in 

 the absence of verricules on the first four abdominal segments. The 

 setae densely cover all parts of the body. Clavate-plumed setae are 

 present only on the prothorax. 0. leucophaea, 0. pini Dyar, and 0. 

 plagiata are more similar to the common Tussock moth. 



Hemerocampa and Notolophus overlap and the larvae can not be 

 distinguished. X. antique differs from the others in the presence of 

 clavate-plumed setae on abdominal segment 2. The others may be sepa- 

 rated by the table given by Dyar in Psyche, 7, 1893, p. 421. 



