1864.] 



77 



species, the one A. virgo Linn., larger, the stripes on the median vein 

 extending on either side beyond the vein itself, the other A. Saun- 

 derxli m., smaller, the stripes on the median vein linear, confined to 

 the vein itself. 



Arctia Persephone, Grote. Plate 1, fig. .3, % . 



A. Persephone, Grote, Proc. Ent. Soc. Phil., Vol. 2, p. 433. 

 The figure is taken from the typical specimen in the Collection of 

 this Society. I have seen a second, perfectly corresponding but smaller 

 individual, in the collection of Jas. Ridings, Esq., Philadelphia. 



Arctia decorata, Saunders. Plate 1, fig. 4, 9 • 



A. deeorata, Saunders, Proc. Ent. Soc. Philad., Vol. 2, p. 60. 

 A. decorata, Saunders, Syn. Can. Arct. p. 11. 

 Eab. Canada. Eastern and Middle States. (Coll. Ent. Soc. Phila.) 

 Mr. A. S. Packard Jr. informs me that he considers this species as Spi- 

 losoma nais Drury, which has however, according to figure and descrip- 

 tion, yellow posterior wings and abdomen. It evidently belongs to a dif- 

 ferent, and as yet undescribed genus from those to which it has hith- 

 erto been referred. A. nais Saunders, as I have ascertained from an 

 examination of the author's specimens, \s=:virgimcula Kirby. I refer 

 to Mr. Saunders' paper for further particulars regarding this species. 



LTPARIDINA, H-S. 



LACOSOMA. nov. gen. 

 % . Anterior wings ample, straight along the costa, broadly sub- 

 falcate , exterior margin rounded, slightly excavated between the 2nd 

 and 3rd inferior veins , internal margin straight ; posterior wings 

 ample, entire, rounded along external margin, anal angle prominent 

 and very slightly projected, internal margin folded, sparsely fringed 

 with long hair. Head small, sunken ; front broad ; eyes small ; an- 

 tennae moderately short, deeply bi-pectinate, pectinations decreasing 

 towards the tips, with a basal tuft. Legs moderately slight, sparsely 

 clothed with long coarse hair ; anterior tarsi naked ; posterior tibiae 

 with two small terminal spurs ; anterior and middle tibiae, unarmed. 

 Neck, below the head, well clothed with long hair ; palpal structure 

 rudimentary ; abdomen cylindrical, compact, evenly clothed with short 

 hair, not crested, anal valves moderately clothed with coarse hair. 9 , 

 not seen ; pterogostic structure not examined. 



