214 THE CANADIAN ENTOMOLOGIST. 



In the Coloradan species the outer surface of all the tarsi is checked 

 with black and white ; in the Long Island £>ne these markings are almost 

 entirely obsolete. The markings of the anterior wings of the former 

 species are more prominent and better defined, the ordinary spots are not 

 so elongate, and are united by a short, thick neck, and the basal dash is 

 shorter and thicker ; otherwise the markings are much the same. 



The female of riparia presents a curious structure of the end of the 

 abdomen, perhaps for the purpose of retaining the male ; the end of the 

 abdomen is bare of scales, but near the tip there is a ring of rather long 

 hairs, followed by a ring of stout curved spines ; such a structure is, so 

 far as I know, unique in the Noctuidae. 



I have not been able to observe the female of chandteri, so that I do 

 not know whether it is armed in the same way. 



DESCRIPTIONS AND NOTES ON THE NOCTUID^. 



BY H. K. MORRISON, CAMBRIDGE, MASS. 



A°rotis decolor Morr. 



\v 



Proc. Boston Soc. Nat. Hist, vol. 17, p. 162. 



Agrotis campestris ( \ n >te. 



Can. Ent., Oct., 1875. 



Having received many additional specimens of this species, I am able 

 to give below a fuller description than my original one, and to compare 

 it with its two allies, geniculates Grote and tessellata Harr. 



A. decolor can at once be distinguished from tessellata by the dark 

 purple ground color, frequently overspread in the median and basal spaces 

 with cinereous, and by the absence of any gray tint ; from ge?iiculata the 

 best character which I have observed to separate it is the color of the 

 thorax, which in decolor is brown, having usually the prothoracic and meta- 

 thoracic tufts yellow, and having always a yellow spot at the base of the 

 tegulae ; in the former the thorax is simply cinereous and black. 



The following are its characters drawn from a large series of specimens 

 from Maine, Canada, New Hampshire, New York and Massachusetts : 



