EARLY VOICES OP SPRING. 21 



he leans to the left ; if scratched on both sides he 

 squats with content, and, I imagine, an expression 

 of satisfaction settles in his fishy eye. 



I do not suppose a toad has any parasite to bite 

 his tough, warty back ; the frog, though, does unfor- 

 tunately have a certain low parasitic form of life 

 which inhabits his blood.* About every creature 

 in the world, however, is likely to furnish another 

 smaller world for yet smaller creatures to live in, and 

 the frog is no exception to the rule. There is more 

 truth than nonsense in the suggestive doggerel that 

 runs : 



" Little fleas have lesser fleas upon their backs to bite 'em, 

 And these fleas have lesser fleas, ad infinitum. 

 Great fleas have greater fleas upon their backs to go on. 

 And these fleas have greater fleas and greater fleas, and 



so on ! " 



* There have been certain sausagelike pai'asites discovered in 

 the blood of Rana esculenta. Dr. Gaule found in this frog's red 

 blood-oorpusoles, mobile corpuscles, elongate, and pointed at the 

 extremities. These issued from the cells, which they could drag 

 after them for some time, but after a while became motionless, and 

 finally died and disappeared. 



