56 The Ottawa Naturalist- |June 



ZOOLOGICAL REPORT 1905-6. 



As a result of the year's work the leaders of the Zoological 

 Branch have the following subjects of interest to lay before the 

 members of the Club. 



Two meetings were held during the early part of the season, 

 the first at the residence of Mr. Halkett, the second at that of 

 Prof. Prince. At the first meeting, held on gth May, 1905, be- 

 sides the chairman there were present Prof. Prince and Messrs. 

 Lemieux, Campbell and Baldwin. Mr. Campbell, of the Collegiate 

 Institute, exhibited specimens ot a salamander in various stages 

 of development. Mr. Halkett followed, shewing prepared speci- 

 mens of the cranium of Menobranchus or the mud-puppy {Nocturus 

 fnaculosus), and illustrated the comparative structure of the 

 cranium of certain fishes by shewing specimens of that of the 

 angler [Lophius piscatorius), the po\\ock.(Po//achius virens) , the cat- 

 fish (Ameiurus nebulosus) and the yellow perch {Perca flavescens). 

 Mr. Baldwin spoke of having seen a black snake (Zamenis co?i- 

 stridor) killed with a stone, some ten years ago, from the wounded 

 placs of which little young snakes made their exit thus drawing 

 attention to the apparent viviparous nature of that serpent. Mr. 

 Lemieux shewed photographs of certain mammals, such as the 

 black bear (Ursus americanus) and the red deer (Cariacus 

 virginianus). Prof. Prince concluded the meeting by reading a 

 paper on the function of the swim bladder of fishes, of which the 

 following is the substance. 



None of the various views generally held, the professor 

 pointed out, regarding the function of the swim-bladder of fishes 

 appears to be perfectly satisfactory. According to these views 

 the swim-bladder is supposed to aid in flotation, giving buoyancy 

 to the fish possessing it, or it acts as a barometer informing the 

 fish as to the pressure of the surrounding water, while it is also 

 regarded as a resounding organ, in connection with the produc- 

 tion of sounds, or again respiratory functions have been attributed 

 to it. In some fishes it has connection with the ears by specially 

 modified bones (the Weberian apparatus), and may aid in audition. 

 Professor Prince stated that the following difficulties in accepting 

 these views existed, viz. : The most buoyant fishes, such as 



