- 



328 



greater shifting and variation of structural characters than in this, and vet ii 

 is nearly always easy to recognize an Acidalia. 



I retain Treitschke's name for the group, as Hiibner's Arrhostia only con- 

 tained five (ml of over one hundred European species, and his views of the 

 genus were vague compared with Treitschke's. Probably fifty or sixty addi- 

 lioual species are to be discovered on this continent. Bui it is to be hoped 

 that isolated descriptions of them will not be published. 



Synopsis of the Species. 



ATLANTIC STATES. 



A. Species small ; fore wings elongated ; hind wings rounded: 



a. Ash-gray; fore wings with four lines beyond the discal dot : 



Fore wings with outer edge convex I. ossulata. 



Fore wings witli onler edge very straight : apex pointed 1. perirrorata. 



b. White, niili »< hreous lim ■ : 



Small: wings narrow; much elongated i. longipennata. 



Like loiigipt nnaia, but wings broader I. peralbata. 



Like peralbata, l>nt larger; submarginal line- often zigzag, and black or 



ochreous A. punctofimbriata. 



c. Fore icings long ; hind icings rounded: 



Larger I nan any of the preceding ; silky-ocbrcous, with slightly darker 



lines 1. productata. 



B. Costa of fore wings very straight, paler than rest of wing; hind wings 



short : (Miter edge less convex than usual: 



Hind wings very short, less convex than usual, triangular ; pale greenish, with 



numerous fine obscure lines .A. insulsaria. 



Reddish tinged with vermilion; costa reddish, and connected with three red- 

 dish transverse lines A. pannaria. 



Like pannaria, but bind « ings as in insulsaria ; costa of fore wings con.spicu- » 



nil sly while 1. albocostaliata. 



C Of large size; hind wings usually angled: hind tarsi short : 



Whitish : no well-marked lines; lure and hind wings much rounded A. rotundopennata. 



Perfectly white; very large; hind wings much bent A.nivosata. 



Hind wings slightly bent, fawn-gray, with four distinct, slightly darker lines.. J. inductata. 

 Like inductata, but brick-red, and more hairy, with dark reddish-brown lines.. J. sentinata. 

 Whitish-ocbreous; hind wings distinctly bent ; two ochreous lines common to 



both wings; smaller than enucleata /. quadrilineata. 



Small. Wings narrow : hind wings very angular 1. cacuminata. 



Fore wings subfalcate ; whitish-ocbreous; hind wings much bent; both wings 



with heavy black lines and patches on the outer tliird A. enucleata. 



Wings subfalcate, nearly white, with two very distinct ochreous lines, common 



to both wings A. ordinata. 



PACIFIC STATES. 



V. Diminutive; hind wings rounded: 



Like- ossulata, granite graj A. granitata. 



