AGROTIS DISCOIDALIS, n. s. 



$. — Fore tibiae unarmed; appearing allied to attenta. Fuscous or 

 wood brown. The geminate lines as usual in this group. Cell black. 

 Stigmata concolorous; orbicular elongate ovate; renifonii upright. Sub- 

 terminal space tiie darkest. Tiie general color is fuscous witii a grey shade 

 except on subterminal space. The distinctive character of this species is 

 the black shading around the orbicular on the cell. There is a trace of the 

 daviform. Hind wings pale fuscous with interlined fringes and the veins 

 marked. Beneath paler with faint line and discal mark. 



Expanse, 34""". No. 5609, Nevada, Mr. Hy. Pldwards. 



Type Locality: Nevada ? (Sierra Nevada according to Sir George 

 Hampson). 



Number and Sexes of Types: 



Types ik: British Museum, 1$. 



Specimens Exa:mixed: Total, 31; from, California; Northern Cali- 

 fornia; Central California; Truckee, and Plumas Co., Calif.; Pyramid Lake, 

 and Esmeraldo Co., Nev. ; ^'^ineyard, Eureka, Provo and Stockton, Utah. 

 One specimen, compared with type by Sir George Hampson, California. 



Gex?;tai.ic vSi.u)Fs: 1, Pyramid I^ake, Nev.; 1, Stockton, Utah. 



This species has been sufficiently discussed under Group Dis- 

 coidalis and Group Mirabilis to need no further discussion, in view 

 of the fact that jNIr. Grote's description is very clear and concise. 



GROUP PLACIDA 



The Placida Group contains one named species and one aberra- 

 tion, viz : placida and ab. minimalis. This is a heterogeneous group, 

 in a most unstable evolutionary state. Scarcely any two specimens 

 of "placida" look alike, and at least minor differences occur in the 

 genetalia of almost every example which the author examined. No 

 single character or group of characters seem stable. The writer 

 prefers to consider "placida" as a name applied to a group, as 

 well as to a single definite species. Grote's type coming from New 

 York, the name might fittingly be applied to I^astern specimens. 

 For the sake of convenience the grou23 name "placida" will have to 

 stand for Western material as well. Eastern placida may vary^ in 

 the same way as Western. It is scarce, coming from the Adirondack 

 Plateau, and only one specimen was available for studj^. 



In the West "placida" reaches its magnitude, producing forms 

 resembling almost every species that lacks a thoracic crest. From 

 the Placida Group appear to have arisen. Eastern placida, sambo, 

 and scopeops as illustrated in the phylogenetic relationship diagram. 

 These species seem separate and worthy of names, as: far as can be 

 judged by our present knowledge. Utah and Colorado material 

 seems to show the greatest instability, probablj^ due to the various 

 environments to be found within limited areas. It is worthy of note 

 that "placida" from Utah often resembles forhesi or ne fascia; New 

 Mexico material resembling nefascia or harnesi; Colorado material, 

 nefasciaj while Vancouver shows forms similar to scopeops. 



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