BUTTERFLIES HERRERA AND FIELD 497 



Length of forewing, 28-32 mm. (average, 29.6 mm.). 



Female genitalia not illustrated, not distinguishable from T. micro- 

 dice. The genitalia of six females were studied. 



Type locality: "Buenos Aires," Argentina. 



Additional type data: Described from a single male specimen, 

 the holotype (locality as given above, December). 



Location of type: Presumably in the collection of M. C. Van 

 Volxem, the whereabouts of which is unknown. 



Method of identification: By comparison with the original 

 colored figure and description. 



Synonymical notes: 



Pieris achamantis Berg, 1875. Type locality, "Cerro de Caballada," Territorj' 

 of Rfo Negro, Argentina. Described from two specimens collected by Francisco 

 P. Moreno and presumably now in the collections of the Museo Argentino de 

 Ciencias Naturales, Buenos Aires, Argentina. This name is clearly a synonym 

 of T. vanvolxemii. 



Tatochila volxerni var. fulva Kohler, 1923. Described from a single female 

 specimen collected in Tucumdn and now in the collection of Alberto Breyer. It 

 represents a slightly melanic individual form in which the submarginal spots on 

 forewing above are confluent and connected to the discocellular spot. 



Tatochila volxerni forma obsura Kohler, 1923. Described from a female speci- 

 men collected in Tucumdn and in the collection of Alberto Breyer. It is an 

 individual form similar to fulva that has a deeper reddish yellow color (presumably, 

 although not stated, on the undersurface of the hindwing). 



Misspellings: Harold (1879) and others improperly emended the 

 spelling of P. or T. van volxemii to P. or T. volxemii. Capronnier 

 very clearly named this species after M. C. Van Volxem. Hayward 

 (1951) was the first to give the proper form of this name. 



Distribution: Argentina from the Provinces of Tucuman and 

 Buenos Aires south into the Territory of E-io Negro. 



Argentina: Province of Tucuman, Tucumdn; Province of La Rioja, La Rioja; 

 Province of Cdrdoba, C6rdoba; Province of Mendoza, Uspallata Mountains (1,850 

 m., October), Potrerillos (1,500 m., October), Mendoza (May, July); Province of 

 Buenos Aires, Medanos (November), Bolivar (December); Territory of Rio Negro, 

 Rio Colorado (October, November), G6mez (December, January), "Chdele" 

 (November). We have seen specimens labeled without specific locality data as 

 coming from both Uruguay and Paraguay. We doubt the authenticity of these 

 labels. 



Material studied: 27 males, 19 females. 



Tatochila mercedis (Eschscholtz) 



Pontia mercedis Eschscholtz, in Kotzebue, Entdeckungs-Reise in die Sud-See 

 und nach der Berings-Strasse, vol. 3, p. 215, pi. 9, figs. 22a, 22b, 1821.— 

 Berg, Anal. Mus. Nac. Buenos Aires, vol. 4, p. 231, Nov. 18, 1895.— Staud- 

 inger, Lepidopteren, in Hamburger MagaLhaensische Sammelreise, vol. 2, 

 art. 6, p. 11, 1898. 



