304 CLARENCE M. WEED. 



crevices between the base of the trunk and larger roots and the soil, 

 or beneath the fallen leaves or other rubbish at the soil surface. 

 Here they remained until Spring, when they took advantage of the 

 first warm days to crawl up the trunk to the twigs. So early as 

 April 9th I found that large numbers had already established colo- 

 nies on the twigs, the pulverulence developing so that many of them 

 had a distinct coating of white. The afternoon of the 9th was cold, 

 and a very few of the young lice were .seen ascending the alder 

 stems. There were a great many yet remaining in the rubbish. I 

 made another observation a week later (Api'il 16th), the afternoon 

 being warm and sunny. Many of the young aphids were then as- 

 cending the alder stems ; nearly all were headed away from the roots, 

 but occasionally one was going sideways, and rarely one was turned 

 toward the roots. Many were yet below, especially where the base 

 of the stems were thickly covered with fallen leaves. The colonies 

 were numerous on the young twigs, but there were none on the old ones. 



Enormous numbers of these young lice must be washed away by 

 the falling rains and melting snow. I found many of them among 

 the stones along a brook, often on the undersides of the stones in the 

 nests of ants (Lasitis) with Dactylopius and the eggs of aphides, but 

 the ants paid no attention to the young Schizoneuras. 



The dead Autumn colonies are almost as conspicuous in Spring as 

 they were the previous Autumn. 



The young as it comes out of Winter quarters in early Spring 

 may be described as follows : 



Young in Spring. — Body 1.2 mm. long; 0.7 mm. wide. General color olive- 

 green, with tips of aTitenuse, tip of rostrum and claws, blackish. Body, includ- 

 ing legs and antennfe, thickly furnished with rather long, stiff hairs, having 

 recurved tips. Six longitudinal rows of pulverulent spots on abdomen, running 

 together on last two segments. Similar spots on head and thorax, but in less 

 distinct rows. The size and amount of pulverulence varies considerably, those 

 on the borders of having less, thus indicating more recent arrival from below. 



The adult viviparous female which in Autumn gives birth to the 

 hibernating form is described as follows: 



Apterous Viviparotis Females. — Body 5 mm. long, 3 mm. wide. Body pear- 

 shaped; abdomen large and swollen; color lead-gray throughout; antennpe light 

 grayish brown, sometimes with a greenish tinge, and terminal joint dusky. 

 Legs brown, with tips of joints black. Antennse very short ; joints iii, iv and v 

 swollen on posterior side; third joint nearly twice as long as second; fourth 

 very short, less than half as long as third; fifth short, a very little longer than 

 third. Segmentation of abdomen very distinct. Rostrum short, robust. Dorsum 

 furnished with a long pulverulent coating. 



I put a number of specimens of this form in empty vials October 

 17th, and during the next five days one of them gave birth to forty 

 young. The appearance of a branch infested by these insects and 

 the fungus which accompanies theni is shown on Plate VII. 



