284 STATE HORTICULTURAL SOCIETY. 



ISCHNOCERUS NIGRICAPITATUS, N. SP. FEMALE. 



The color is black marked with brown. The 

 head is smooth, shining black with a very line 

 pubescence. The antennae (Fig. 7) are long, 

 recurved, and slightly enlarged toward the ends. 

 Each antenna? has twenty-seven joints. The scape 

 and the two or three following joints are honey, 

 yellow, but each succeeding joint is more dusky 

 The entire club is dusky. The labrum is yellow- 

 ish, mandibles brown, and the palpi whitish. The ' 



entire thorax, like the head, is intense black. pi g . 7— Female. Abdomea side 

 The parapsidal grooves are distinct. The meso- view - 



thorax has very fine transverse striae, and is finely pubescent. The meta- 

 thorax is sub-quadrate, faintly rugulose, and pubescent. The tegula? are 

 whitish; the wings hyaline, iridescent, and slightly pubescent. The venures 

 and stigma are dusky, except at base where they are whitish; legs yel- 

 lowish brown except knees and tip of last tarsi which are dusky. The 

 abdomen is petiolate, broad, and hairy. The first segment is black, longi- 

 tudinally striate, and broadens abrubtly beyond the middle. The second, 

 third, and fourth segments are brown. The lateral margins of the second 

 and the broad lateral and narrow posterior margins of the fourth are dusky. 

 The fifth and sixth segments are dusky, with a slight posterior brownish 

 border. The ovipositor is brown, the guides black. Length three thirty- 

 seconds of an inch. 



THE PEACH LOUSE — APHIDIUS. 



The past season — 1890 — the common peach-louse, Myzus persicss, was a 

 ■serious pest in many parts of Michigan. This well-known aphis is only 

 one twelfth of an inch long. The body is greenish black, marked with 

 Mack. The antenna? are black and the abdomen and legs yellowish brown, 

 the latter marked with black. These lice work on the under side of the 

 leaves which they cause to roll up or curl. The leaves become pitted 

 beneath and bunched above, and soon fall from the trees. The past season 

 •one of my pupils, Mr. C F. Baker, reared a large number of Braconid 

 parasites from these lice. The parasites served greatly to reduce the 

 number of lice, and it is to be hoped that they will prove as efficient as did 

 the closely related Aphidius granariaphis in clearing the grain fields of the 

 grain louse in the summer of 1889. This proves to be a new species so far 

 as I can ascertain. 



In this species the abdominal segments are quite freely movable, so that 

 the abdomen bends readily under the thorax. The venation of the posterior 

 wings is very simple, indicating the sub-family Aphidiina?. The first dis- 

 coidal cell is incomplete. The abdomen is lanceolate, the antenna? fifteen- 

 jointed, and so we have the genus Aphidius. 



APHIDIUS PERSIAPHIS, N. SP. — MALE. 



This species (Fig. 8.) is black with scattering lightish hairs. The head is 

 smooth, shiniug black, and very slightly hairy. The compound eyes and 



