82 STUDIES OF ANIMAL TYPES 



in the posterior part of the body cavity, and in close con- 

 tact with the dorsal wall. Each one opens into the cloaca 

 through a delicate duct, the ureter. A urinary bladder 

 opens into the cloaca on its ventral side. 



Reproductive organs. Find the two ovaries of the female 

 that lie anterior to the kidneys. They are irregular, oval 

 bodies, with their surfaces raised up into rounded eleva- 

 tion, showing the position of the ova. The oviducts are 

 wide tubes that open into the body cavity at their anterior 

 ends, while their posterior ends open into the cloaca just 

 in front of the ureters. 



The two spermaries of the male are white oval bodies 

 in about the same position as the ovaries. The sperm 

 ducts open into the ureters. 



XXIII. THE ENGLISH SPARROW 



Materials. Specimens of English sparrows, cotton, chloroform, 

 pine board, tacks, dissecting instruments, pins, apparatus for in- 

 flating (see Ex. XXI). 



Directions. (Since these birds have become a pest, no com- 

 punction will be felt in killing what are needed for this work. It 

 will be best to catch them alive.) 



A. EXTERNAL FEATURES. Note the shape of its body. 

 Is the body divided into the same parts as that of a frog 

 or lizard? How many legs has the sparrow? How do 

 they differ from those of the frog ? How does the anterior 

 pair of appendages differ from the fore legs of a frog ? It 

 must be remembered that these are homologous organs. 

 What is the body covered with ? Are the feathers of uni- 

 form thickness all over the body ? 



Note the shape of the wing. Note that they are attached 



