CORRODENTIA, 99 



and watch the pale tiny creatures that scurry across its 

 pages; examine one of them with a lens, look well at his 

 alert, knowing, black eyes, and we are sure you will believe 

 that he is in search of real literature, and not merely a feeder 

 upon paper, as we are taught. Anyway, scientists have con- 

 cluded that these insects look wise enough to bear the name 

 Atropos divinatoria (At'ro-pos di-vin-a-to'ri-a), 

 or the Divining Atropos (Fig. 108). They 

 are, however, more commonly called simply 

 book-lice. 



Some members of the family Psocidae do 

 not live in books, but feed upon lichens that 

 are found on the trunks of trees and on fences, FIG. 108. 

 often a great number being grouped together. 

 Many of these have wings, and look like plant-lice (Fig. 107). 

 The eggs are laid in heaps on leaves and branches, and are 

 covered with a tissue of threads ; for the Psocids have the 

 power of spinning silk similar to that spun by spiders. 



