The CANADIAN ENTOMOLOGIST. KH 



been asserted for a generation or two to be preoccupied. I am glad, indeed, 

 to learn (Sherborn's Index Animalium, quoted by Bezzi, Wien. Ent. Zeit., 

 XXVI, 53), that the use of the term Psilopus by Poll in Mollusca in 1795 

 was not in a nomenclatural sense, and hence does not constitute a pre- 

 occupation of the name, which should therefore stand for the dipterous 

 genus. 



WISCONSIN BEES — NEW AND LITTLE KNOWN SPECIES. 



BY S. GR^NICHER, PUBLIC MUSEUM, MILWAUKEE. 



Perdita F. Smith. 



In the eastern part of Wisconsin this genus is poorly represented. In 

 the region around Milwaukee only two species have been met with so far, 

 one of these P. maura Ckll., and the other a new species described below. 

 Along the St. Croix River, in the north-western corner of the State, three 

 species were obtained (Milw. Publ. Mus. coll. exped.), two of which are 

 new, while the third, P. Brwieri Ckll., had up to the present time not been 

 found farther east than Nebraska. It is more than probable that careful 

 collecting along the western border of Wisconsin will add some more 

 species of Perdita to the bee fauna of our State. 



Perdita paUidipennis, n. sp. 



Female. — Length about 8 mm. This is a third member of the 

 olbipennis/acteipennis group. Head and thorax blue-green. Front and 

 vertex dull, face, thorax and abdomen shining. Mandibles curved as in 

 albipennis, with reddish tips. On the clypeus a yellow spot on each side 

 in addition to the cuneate-yellow median line. Adjoining the clypeus a 

 yellow mark on each side of the face. Scape in front, a line on prothorax, 

 and tubercles yellow. Flagellum black, a trace of reddish rear the tip. 

 Legs dark, with no yellow markings, except on the knees of front and 

 middle legs. Tegulae yellowish on the upper half, brown below. Wings 

 white, nervures and stigma pale. Abdomen black, usually lighter on the 

 apical depressions of the segments. On the first segment a small yellow 

 dot on each side, situated on the margin. A subbasal yellow band, 

 narrowed medially, on each of the four succeeding segments, interrupted 

 on segments 2, 3 and 4, or at least on 2 and 3. Pygidiura dark brown, 

 shining. Pubescence of vertex and mesonotum yellowish and erect, long 

 on the vertex, short on the mesonotum. On cheeks and pleurse the hairs 

 are white and long, those on the legs of a dirty-yellow colour. 



April, 1910 



