42 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 82 



terior spots, and the elytra with narrow vittae. The undersurface 

 sometimes entirely pale or with only the metasternum dark. Length, 

 7 to 8.2 mm. 

 Type locality. — ^Wyandanch, N.Y. (one paratype, U.S.N.M. No, 



44117). 



Distrihution. — ^Wisconsin (Cranmoor) ; Minnesota (Mora) ; Illi- 

 nois (Chicago) ; Michigan (Lake Douglas) ; New York (Wyan- 

 danch) ; New Jersey; Maine (Casco Bay) ; New Hampshire; Massa- 

 chusetts (Chicopee, Springfield) ; Nova Scotia (Truro). 



Remarks. — Mr, Schaeffer has sent me a paratype of laticolUs from 

 Wyandanch, N.Y., which he has donated to the National Museum, 

 and two other specimens from Casco Bay, Maine, both of which 

 belong to the same species. 



D. latifrons., like D. anzonae and D. fumata^ has a wide range, and 

 varies in size and degree of coloration in different localities. The 

 Rocky Mountain specimens usually have a more or less darkened 

 undersurface. The Canadian specimens have larger pronotal spots, 

 and the eastern specimens are larger and paler. No sharp line can 

 be drawn between these various races, since their geographic distri- 

 bution is continuous from Arizona to British Columbia in the Rocky 

 Mountains, and eastward through the provinces of Canada and 

 through the Northern States to Nova Scotia, Maine, and New Jer- 

 sey. The aedeagus of specimens from Montana does not differ except 

 in size from that of specimens from Massachusetts. 



Var. asteris was collected by J. B. Wallis on white aster in Alberta. 

 In Nova Scotia W. E. Whitehead ^^ reared the eastern variety, 

 laticolUs, from Solidago squarrosa, and in Massachusetts George 

 Dimmock collected it on S. altissinia. Like D. fimiata, it is evi- 

 dently a feeder on Compositae. 



Like fumata and caroliniana, latifrons is oval and has a distinctly 

 convex prothorax. The western and Canadian varieties are easily 

 distinguished from fumata by the dark undersurface. The eastern 

 paler variety has been confused in collections with caroliniana. D. 

 oaroliniana nearly always has a pale labrum, while that of latifrovs 

 is always dark. Moreover, latifrons is generally larger and broader 

 proportionately. The head is unusuiilly smooth and unbroken by 

 swelling of the frontal tubercles or carina. D. fumata has a much 

 narrower head with the frontal tubercles and interantennal convexity 

 well marked. The aedeagus of latifrons somewhat resembles that 

 of fumata, but has a broader tip, and is quite different from the 

 aedeagus of caroliniana. 



=« Whitehead, Nova Scotia Ent. Soc. Proc, 1918, p. 38. I have examined specim*>na 

 from which this record was made and found them to be D. laUjrons var. laticolUs. 



