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VOL. XXII. 



LONDON, JULY, 1890. 



No. 



APHIDIUS GRANARIAPHIS, n. sp. 



BY PROF. A. J. COOK, AGRICULTURAL COLLEGE, MICHIGAN. 



Black above, yellowish brown beneath. The antennae are black, the 

 front, mouth parts and legs yeUowish brown. Rarely the femora and 

 tarsi are dusky, and the ventral surface quite dark. Very rarely the dorsal 

 surface is brownish, except the pedicel and tip. The occiput or collar is 

 brown. The antennas are sixteen jointed in the female, and seventeen in 

 the male, and are cylindrical, recurved, and thickly set with short, light 

 colored hairs. The first two joints are shorter and larger than the others ; 

 the succeeding joints are cylindrical, close together, and equal in length, 

 except the last, which is longer and conical. The abdomen is lanceolate, 



and all the segments are freely moveable on each 

 other, so it can be easily bent under the thorax. 

 The venation of the wings — see figure — is simple, 

 and the first discoidal cell incomplete. We know 

 from the simple venation of the wings that this is 

 a Braconid. It belongs to the genus Aphidius, 

 as the first discoidal cell is incomplete, the abdo- 

 men lanceolate, the antennse sixteen or seventeen- 

 ' jointed, and the ventral valves in the female 

 simple. It is 2^4, mm. {i-io in.) long. 



This species differs from Aphidius avenaphis 

 Fitch, as that species has nineteen or twenty joints 

 to the antennse, is honey yellow where this is brown, and the first two 

 joints of the antennee, the pedicel of the abdomen, and a spot on the su- 

 ture between the first and second joints of the abdomen are honey yellow 

 and not black as in Granariaphis. The joints of the antenna are also less 

 pedicelated, or closer together than in the Avenaphis. 



This species is interesting from the fact that it was the principal agent 

 in exterminating the coundess millions of grain Aphides last season — 1889 

 -—in Michigan and adjacent States. While Aphidius avenaphis and other 

 enemies, fike Syrphus flies, Coccinnelids and Chrysopa fly larva? were 



Fig. 3. 



