INSECTS INJURIOUS TO THE WILLOW. 



THE SPOTTED WILLOW-APHIS. 



( Lachnus dentatus, n. sp. ) 

 Order of HOMOPTERA. Family of Aphid^e. 



Found in flocks, in October and November, on the under side of the 

 branches of the gray willow. They were also found in smaller num- 

 bers on the trunks of small nursery apple trees, standing about a rod 

 from the willows. When crushed, they stain the fingers with a thick 

 reddish fluid. 



Length, two-twelfths of an inch; expanse of the wings, sLx-tenths. Black; abdomen, 

 dark ash-colored, with six transverse rows of black dots. Antennaj, filiform, as long as the 

 head and thorax; two basal joints, short and stout, the third as long as the three terminal 

 ones united; these three equal. Proboscis, greenish-yellow at base. Fore wings, with the 

 usual stout sub-costal vein, and a very elongate stigma; three discoidal veins, (exclusive of 

 the stigmatic vein,) much wider apart at their tips than at their bases; third vein, two-forked; 

 hind wings with a sub-costal and two discoidal veins, the latter very closely approximate at 

 base and divergent at tip. Thighs, dark honey-yellow, broadly tipt with black; tibiaj, dusky; 

 reddish at the base. 



The honey-tubes are sub-obsolete. The dots on the abdomen are very distinct, especially 

 on the fully-grown, wingless individuals. In the intermediate rows, the dots are six in num- 

 ber, the two middle ones being smaller than the others. Just behind the middle of the abdo- 

 men, and occupying the place of the two middle dots in the fourth row, is a somewhat con- 

 spicuous black, coniotil protuberance, varying in size in different individuals, and sometimes 

 considerably more prominent than it is represented in the figure. 



