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ZOOLOGICAL SOCIETY BULLETIN. 



ZOOLOGICAL SOCIETY BULLETIN. 



Elwin R. Sanborn, Editor. 

 StparlmtntB : 



Reptile 

 Raymond L. Ditmars. 



Bird 

 C. William Beebe. 



Mammal 



VI. T. HORNADAY. 



Aquarium 



C H. TOWNSEND. 



Raymond C. Osburn, Ph. D. 



Lee S. Crandall. 



Published Bi-Monthly at the Office of the Society, 



11 Wall Street, New York City. 



Single Numbers, 10 Cents ; Yearly, by Mail, 70 Cents. 



MAILED FREE TO MEMBERS. 



Copyright, 1911, by the New York Zoological Society. 



Numhek 48 



NOVEMBER, 1911 



UDffirrra of tli» Society. 



Jirruturiit : 

 Henry Fairfield Osborn. 



Exrruttur ffloinmtttrr : 



Madison Grant, Chairman, 



John S.Barnes, Samuel Thorne, William White Niles, 



Percy R. Pyne, Levi P. Morton, Wm. Pierson Hamilton, 



Frank K. Sturgis, 



Henry Fairfield Osborn, Ex-Officio. 



(ftmrral Wffirrra : 



Secretary 



Madison Grant, 11 Wall Street. 



Treasurer 



Percy R. Pyne, 30 Pine Street. 



Director 



William T. Hornaday, Zoological Park. 



Director of the Aquarium 



Charles H. Townsend, Battery Park. 



Boaro of Ifluuaun u : 



Ex-Officio 



The Mayor of the City of New York 



Hon. William J. Gaynor. 



The President of the Department of Parks 



Hon. Charles B. Stover. 



(Claim of 1912. 



Levi P. Morton, Samuel Thorne, 



Andrew Carnegie, Henry A. C Taylor, 



John L. Cadwalader, Hugh J. Chisholm, 



John S. Barnes, Frank K. Sturgis, 



Madison Grant, George J. Gould, 



William White Niles, Ogden Mills. 



ffilana of 1913. 

 F. Augustus Schermerhorn, Frederick G. Bourne, 

 W. Austin Wadsworth, 

 Emerson McMillin. 

 Anthony R. Kuser. 

 Watson B. Dickerman, 

 Mortimer L. Schiff. 



Percy R. Pyne, 

 George B. Grinnell, 

 Georce C. Clark, 

 Cleveland H. Dodge, 

 C. Ledyard Blair, 



(Ilium of 1914. 



Henry F. Osborn, James J. Hill, 



William C. Church, George F. Baker, 



Lispenard Stewart, Grant B. Schley, 



H. Casimir de Rham, Wm. Pierson Hamilton, 



Hugh D. Auchincloss, Robert S. Brewster, 



Charles F. Dieterich, Edward S. Harkness. 



(Bffirfra of the Zoological Parh : 



W. T. Hornaday, Sc. D., Director. 



Chief Clerk and Disbursing Officer 

 Curator of Reptiles. 

 Curator of Birds. 

 Assistant Curator of Birds 

 Veterinarian and Pathologist. 

 Chief Forester and Constructor. 

 Editor and Photographer. 

 Civil Engineer. 



H. R. Mitchell 

 Raymond L. Ditmars 

 C. William Beebe 

 Lee S. Crandall 

 W. Reid Blair, D.v.s. 



H. W. MERKEL - 



Elwin R. Sanborn 

 G. M. Beerbower 



lilffirrro of trjt Aquarium 

 Charles H. Townsend, Director. 

 Raymond C. Osburn, Ph.D. - - - Assistant Director. 



Chapman Grant Assistant 



W. I. DbNyse In Charge of Collections. 



Robert Sutcliffe ... . clerk 



HOW FISHES BREATHE. 



Respiration is, of course, necessary to every or- 

 ganism, plant or animal, that is to say, oxygen is 

 required for the combustion of the food materials 

 and by this process the organism releases the 

 energy necessary to the activities of protoplasm. 

 Animals var}' widely in the amount of oxygen 

 required to maintain life. Since the constant 

 high temperature of the warm blooded animals 

 requires a great amount of combustion, the birds 

 and mammals consume more oxygen than cold 

 blooded forms. The reptiles and amphibians of 

 the tenrperate regions of the world hibernate dur- 

 ing the winter and during this season of inactiv- 

 ity respiration is greatly lowered. Many species 

 of fishes also hibernate during the colder months, 

 some forms burying themselves in the mud. 



Air breathing animals find a ready supply of 

 oxygen in the air from which they absorb it 

 into the blood through the lungs, or as in the 

 amphibians, partly by means of the thin, moist 

 skin. Animals living in the water have an 

 equally constant, but much less abundant sup- 

 ply of oxygen to draw upon, since water will 

 absorb only a small proportion of this gas. 

 Numerous groups of air breathing animals are, 

 of course, able to live in the water by coming to 

 the surface occasionally to breathe. 



Many of the lower groups of invertebrates 

 present a sufficiently large proportion of body 

 surface to the water so that no special organs 

 for the absorption of oxygen are necessary, e. g. 

 protozoa, hydroids, jellyfishes, corals and most 

 worms. Others, such as the tube-dwelling 

 worms and the molluscus and crustaceans which 

 are encased in hard coverings, have evolved spe- 

 cial expansions of the body, the gills, for res- 

 piratory purposes. In some cases these gills 

 are freely exposed to the water but in most crus- 

 taceans and molluscs the water is caused to flow 

 through special chambers containing the gills. 



The vertebrates have evolved a gill mechanism 

 which is so characteristic of the group that it is 

 found not only in the lowest orders, acorn 

 worms, ascidians and amphioxus, but also in the 

 embryonic stages of reptiles, birds and mammals 

 where they are never functional as breathing 

 organs. This apparatus consists of a series of 

 slits or apertures through the body wall leading 

 from the pharynx to the outside. In respira- 

 tion the water is taken into the mouth and forced 

 out through these slits, coming into close relation 

 with the blood in the walls of the gills. In the 

 acorn worms and amphioxus the gill slits are 

 very numerous, but as efficiency becomes greater 

 the number is reduced. In the lampreys the 

 number varies from seven to fourteen. In the 



