226 THE CANADIAN ENTOMOLOGIST. 



these localities there is enough intergrading in color to show the affinity 

 of the different forms. 



Note. — Varieties 4, 5 and 9 are in the cabinet of Mr. W. G. Wright, 

 of San Bernardino, Cal. I think 4 and 5 were obtained by him from Mr. 

 James Behrens, of San Francisco, and probably both were from Northern 

 California. 



THE NOCTUID^ OF NORTH AMERICA AND EUROPE 



COMPARED. 



(Fourth Paper.) 



BY A. R. GROTE, A. M., BREMEN, GERMANY. 



Tribe Arzamini. 

 The pale or yellow coloured species of Gortyjia, the caterpillars being 

 internal feeders, pupating, however, in the ground, prepare us for the 

 Nonagriini. We have, however, in North America, a peculiar tribe which 

 I have called Arzamini^ and which I here interpolate. The caterpillar 

 was first discovered by Prof Comstock, in Florida Lakes, in the leaf-stalks 

 of the pond lily. This was the larva of A. vuhiifica var. inelatiopyga, 

 and subsequently in the lake at Ithaca, the larva of the typical vulnifica 

 was observed by the same distinguished entomologist. The larva is 

 furnished with nine pairs of spiracles, and passes freely on the water from 

 one leaf to another. Subsequently, the larva of Sphida obliquata was 

 described by Prof. Kellicott. The moths of this tribe are related to the 

 Nonagrians, but differ by the bluntly terminating abdomen of the female, 

 recalling certain LacJmeince. in appearance. There are two genera : 

 Arzama, with three distinct species (of which I owed specimens of A. 

 diffusa to my excellent friend Mr. Moffat) in which the front is smooth, 

 and Sphida, with the single species obliquata, in which the front is 

 tuberculate. This appears not to be a variable or sexual character in the 

 moths, as it may be in certain Scarabeidce, but is in Lederer's opinion, 

 with which I agree, of generic value. If we are not so to consider the 

 tibial armature, or the conformation of the clypeus in the Noctuidce, there 

 remain few characters which we may use as generic. I am disposed to 

 consider, then, Copimamestra, which differs from Mamestra by the tibial 



