Studies of North American Bees 113 



Cockerell referred A^. pilosiila to the genus Viereckella, after 

 having examined specimens of both sexes from Milwaukee, Wis- 

 consin, sent him by Graenicher (see Proc. U. S. Nat. Mns., 

 XXXIX, p. 649), and also pointed out some of the more im- 

 portant characters of Viereckella males. Later, he reiterated this 

 reference of the species, and recorded it from Rlummers Island. 

 Maryland, July 5, 1909, where specimens were collected by J. C. 

 Crawford (ibid., XLI, p. 232). The writer has seen these speci- 

 mens in the U. S. National Museum, and they are the same as 

 Graenicher's species. Through the courtesy of Dr. Graenicher 

 the writer has been able to make direct comparisons of the type 

 of obscura with two females of T^. pilosula from Solon Springs 

 and Maiden Rock, Wisconsin, and after much study believes 

 them to be distinct though exceedingly close. V. obscura is 

 distinctly larger, has somewhat darker wings with the second 

 submarginal cell distinctly longer (in pilosula this cell is distinctly 

 shorter than the first or third), the third antennal joint a shade 

 shorter (in pilosula this joint is about two-thirds as long as the 

 fourth), the hind tibiae within with dark hairs (not obvious in 

 pilosula), and the pygidium less elongate (elongate acuminate in 

 pilosula). It is doubtful if V. ceanothina Ckll. is distinct from 

 V. pilosula. It might be added that Graenicher's determination 

 of r\ pilosula is undoubtedly correct, as Yiereck compared a 

 specimen from Milwaukee with Cresson's New York type. In 

 Wisconsin Graenicher has captured both sexes of V. pilosula, at 

 the places already mentioned and in other localities in that state, 

 and finds the bee is not rare during July- and early August at 

 flowers of Rudbeckia hirta, Aster macrophyllus and Aster fur- 

 catus. (See Bull. Milwaukee Public Mus., I, p. 241.) V. 

 ceanothina was collected at flowers of Ceanothus. At the time 

 the writer described this genus he referred it to the family 

 Melectidae because of its five-jointed maxillary palpi, bluntly 

 rounded marginal cell with its apex away from the costa, lack of 

 tegumentary ornaments, etc., but though resembling the melectids 

 in many ways the genus seems certainly to be Nomadine in its 

 affinities. It closely resembles the recently described genus 

 Nouiadosouia Rohwer, in many respects. 



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