The Frogs and Toads Found in the 

 Vicinity of New York City. 



By William L. Sherwood. 



To describe a class of animals and to collate such informa- 

 tion as is of general interest, one finds it necessary to refer to 

 text books and difficult to avoid using the terms there em- 

 ployed. Some of the descriptions in the following paper will 

 be found to be couched in language taken from such sources, 

 with additions suggested b}^ personal observation. Rather 

 than frequently quote short clauses or single adjectives, the 

 writer prefers to state at the beginning that he is indebted to 

 Professor Cope's " Batrachia of North America" for many 

 parts of descriptions, which could not be expressed in better 

 language than that found in the book mentioned. 



The batrachians l differ froni all other vertebrates in having 

 both gills and lungs, the former persisting throughout life in 

 some of the tailed forms,* as the sirens and mud-puppies of the 

 United States and the Proteus of Europe. After leaving the 

 egg there is a more or less prolonged gill-bearing period. 2 



This is accompanied by a metamorphosis which involves 

 changes from a fish-like form, without limbs or functional lungs, 

 to an adult with four limbs and with lungs. The batrachians 

 share with the reptiles in having cold blood, owing to it not being 

 fully oxygenated as in the birds and mammals. The heart 

 has three cavities, two auricles and a ventricle. The venous 

 blood enters the right auricle from a cavity called the sinus 

 venosus and passes into the ventricle, -where it is mixed with 

 aerated blood from the left auricle, which in turn has received 

 this from the lungs. The mixed blood passes from the ven- 

 tricle through a bulbous cavity known as the truncus arterio- 

 sus, from which it is propelled in part to the lungs for further 



1 Batrachos, frog. 



2 Salamandra atra of Europe forms an exception, the young being 

 brought forth fully formed, although possessing gills in the mother. 



