62 Proceedings of the Biological Society of Washington. 



probably do occur in this country has been my belief for a con- 

 siderable time because of the evident possibility of some of the 

 early spring species having been shipped here in winter or early 

 spring, either in earth used as ballast or around potted plants, 

 during the period when such imports were uninspected on 

 arrival . 



Provided a species obtained access to this country under such 

 conditions it could establish itself very readily if the plants 

 upon which it depended for pollen were available. Most of the 

 early spring species of western Europe, and particularly of 

 Britain, depend upon willow, dandelion, coltsfoot, furze, and 

 various fruit blossoms, for their food supply. Most of these 

 plants are found in New England, and, in fact, throughout the 

 United States, so that conditions in so far as food supply is 

 concerned are favorable. It is of course improbable that speci- 

 mens of imported species would come singly, as they usually 

 nest in colonies, and a spadeful of earth may carry twenty speci- 

 mens and contain both sexes. 



The species which I record herewith is one that occurs through- 

 out Europe and is one of the earliest visitors to willow flowers. 

 I have dug imagines of both sexes out of a sand bank in Scot- 

 land before the middle of March. They were at a depth of 

 about eight inches. 



Saunders uses for this species Kirby's name ivilkella, differing 

 from Schmiedeknecht, who used the same author's species name 

 'jcanthura. The species is known in this country under the name 

 winkleyi Viereck. 



I have before me a series belonging to my own collection, 

 obtained in Britian, which I have compared with a long series 

 submitted for identification from Cornell University, obtained 

 at Ithaca, Rochester Junction, Rock City, and McLean Bogs, 

 New York. The species is intermediate between Robertson's 

 subgenus Trachandrena and Andrena, the male having the third 

 antennal joint very much shorter than the fourth, and the 

 hypopygium very similar to that of claytoniae and allied species. 

 The metathoracic enclosure is similar to that of cressoni Robert- 

 son, and the female resembles the latter very strikingly. The 

 abdomen has the surface so closely and coarsely shagreened.that 

 it has the appearance of having a secondary punctuation at base 

 and apex of each dorsal segment in addition to the large punc- 



