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ON A SPECIES OF BARK LOUSE AFFECTING THE TULIP TREE. 



BY A. J. COOK, LANSING, MICH. 



From the Canadian Entomologist. 



On page 218 of the ''Revised Manual," in speaking of other sources than flowers from 

 which bees collect sweets, I remark that I have seen the bees thick about a large bark louse, 

 which attacks and often destroys one of our best honey-trees. This is an undescribed species 

 of the genus Lecanium. 



In the summer of 1870, this louse, which, as far as I know, has never yet been described, 

 and for which I propose the above very appropriate name, tulipiferoe — the Lecanium of the 

 tulip tree — was very common on the tulip trees about the College lawns. So destructive 

 were they that some of the trees were killed outright, others were much injured, and had not 

 the lice, for some unknown reason, ceased to thrive, we should soon have missed from our 

 grounds one of our most attractive trees. 



Since the date above given I have received these insects, through the several editors of 

 our excellent bee papers, from many of the States, especially those bordering the Ohio river. 

 In Tennessee they seem very common, as they are often noticed in abundance on the fine 

 stately tulip trees of that goodly State. In the South this tulip tree is called the pop- 

 lar, which is very incorrect, as it is in no way related to the latter. The poplar belongs 

 to the willow family ; the tulip to the magnolia, which families are wide apart. ^ 



Whenever the tulip-tree lice have been observed sucking the sap and vitality from 

 the trees — there the bees have also been seen, lapping up a sweet juicy exudation, which 

 is secreted by the lice. In 1870 I observed that our tulip-trees were alive with bees and 

 wasps, even as late as August, though the trees are in blossom only in June. Examina- 

 tion showed that the exuding sweets from these lice were what attracted the bees. This 

 was observed with some anxiety, as the secretion gives off a very nauseating odour. 



The oozing secretions from this and other lice, not only of the bark-louse family (Coc- 

 cidaa), but of the plant-louse family (Aphidae), are often referred to as honey -dew. Would 

 it not be better to speak of these as insect secretions, and reserve the name honey-dew for 

 sweet secretions from plants, other than those which come from the flowers. 



The fact that this insect is yet undescribed — that it attacks one of our best honey 

 trees and is the source of a so-called honey-dew, leads me to append the following descrip- 

 tion, with illustrations. 



NATURAL HISTORY OF THE LECANIUM TULIPIFER^. 



^ The fully developed insect, like all bark-lice, is in the 'form of a ^cale (fig. 1), closely 

 applied to the limb or twig on which it works. This insect, like most of its genus, is 

 brown, very convex above (fig. 1), concave beneath (fig. 2). On the under side is a cot- 

 ton-like secretion, common to all of the genus Lecanium^ which serves to enfold the eggs. 



