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THE CANADIAN ENTOMOLOGIST 



The type of Hesperapis (H. larrce Ckll.) was described as parasitic, but 

 Prof. Cockerell writes that such idea was erroneous. None of the carinata 

 females were carrying a full load of pollen, although two seem to have a small 

 amount which had been moistened. I believe it is a regular Helianthus bee 

 and that it was yet early for them to be collecting. The day was not very 

 favorable although some species of Perdita and Andrena were busily collecting 

 on the sunflowers. None of the females had been found on a warm, windy 

 afternoon two days before (two males on each day). This, the fourth visit to 

 the place, was made later this year, bearing in mind the general rule of protandry 

 and the extreme case of the closely related Rhophites as cited by Friese (Zool. 

 Jahr., 1890). Several males were taken Aug. 10, 1919, inactive on the sun- 

 flowers' heads all day. 



Fig. 1. Hesperapis carinata, female; a, forewing; b, hind basitarsus in cross-section; c, 

 sixth dorsal segment of abdomen. 



Perdita tridentata Stevens. 

 1919. Perdita tridentata Stevens, Can. Ent. 51:206, male. 



Female. — Length about 6 mm. Similar to the male; head and thorax 

 bronzed greenish blue, clypeus, legs and abdomen dark brown. F'ace without 

 yellow markings, mandibles reddish, antennae yellowish beneath, brownish 

 above; abdomen with transverse yellow spots on second and third segments, 

 the first usually with smaller ones; fore tibiae with a yellow stripe. 



Sixteen specimens at Helianthus petiolaris in the sand hills near Sheldon, 

 N. D., Aug. 28, 1920. Allotype No. 12662. The spots on first segment are 

 sometimes absent or nearly so, sometimes proportionately as large as the others, 

 which are separated by a space about equal to their length. The females were 

 collecting pollen. It took also 5 males, and on Aug. 10, 1919, at same place on 

 the same flowers, 2 males. 



This seems to be close to sexmaculata Ckll. (1895) and its var. punctata 

 Ckll. (1896), but I judge probably distinct. It has no spots on segment 4, 

 mandibles not yellow, stigma hyaline medially, cubital and discoidal nervures 

 not especially produced, tarsi all dark. Mr. E. T. Cresson Jr., has compared 

 specimens with the type of sexmaculata and reports: "tridentata has more 

 granulose bronze vestiture; the other being polished with scarcely any bronze. 

 Sexmaculata abdominal spots are round or slightly transverse, and are also 

 present on segs. 4-5. Its fore tibiae are yellow in front and black behind." 



Agapostemon viridulus (Fab.) 

 Fargo, Nicholson. Monango, Glen CUin, Mott, Marmarth, Dickinson 



