121 



due to an error on the part of Mabille (Gen. Insect. Hesp. p. 82) who 

 placed syrichtus Fabr. in his section Pyrgus of Hesperia diagnos- 

 ing it as ' $ with costal fold but without hair pencil on hind tibiae' 

 whereas as Dr. Dyar has pointed out (1. c. p. 117/8) syrichtus possesses 

 both. Unfortunately Dr. Dyar has overlooked the fact that syrichtus 

 is the type of the genus Pyrgus and has removed syrichtus to Helio petes 

 instead of rather removing the other species from Pyrgus. 



With regard to the fixing of the type of Pyrgus Tutt claims 

 (Brit. Butt. I, p. 85) that Stephens in 1834 and 1850 fixed the type as 

 malvae L. Both the works cited however are Lists of British Butter- 

 flies, the former being 'An Abstract of the Indigenous Lepidoptera 

 contained in Hubner's Verzeichniss' and the latter a mere 'Catalogue 

 of the British Animals in the British Museum' and we entirely agree 

 with Bethune Baker (1914, Ent. Record, XXVI, 133) in not accept- 

 ing Stephen's action as being in any way of the nature of a restriction 

 but as merely an 'ordinary usage without references'. This would 

 render Butler's action in 1870 in specifying syrichtus as the type per- 

 fectly valid. With regard to Scelothrix Ramb. Scudder states (1875, 

 Hist. Sketch, p. 266), without designating any type, that the name falls 

 before Hesperia Fabr. The type of this latter genus must appar- 

 ently be accepted as malvae L., due to Cuvier's action in 1799 {vide 

 Tutt, Brit. Butt. I, p. 84, 220), the later designation of comma L. as 

 type being apparently ultra vires on account of Cuvier's restriction ; 

 it would be well then to fix the type of Scelothrix Ramb. definitely as 

 malvae L. so that Scudder's action may be substantiated. Dyar states 

 that there are no species of Hesperia in N. America but this error is 

 evidently caused by his selecting Mabille's first section of Hesperia 

 as typical instead of his last section which contains malvae L. ; Dyar's 

 genus Scelothrix must therefore be changed to Hesperia; we might 

 note that scriptura shows no costal fold in the $ and differs slightly 

 from the other N. American members of the genus in the squammation 

 of the palpi ; it may fall into one of Tutt's doubtful genera erected on 

 p. 218 of British Butterflies, Vol. I. Heliopetes as used by Dyar is 

 correct except that syrichtus and philetas must be removed; these 

 should be placed in the genus Pyrgus and for the present we feel inclin- 

 ed to include with them tessellata Scud, and occidentalis Skin, which 

 only differ in lacking the hind tibial pencil of hairs in the $ (Tutt has 

 proposed the genus Muschampia (1. c. p. 218) for this group). A bet- 

 ter means of separation of Pyrgus from Hesperia (Scelothrix) than 



