ELISHA MITCHELL SCIENTIFIC SOCIETY. 21 



57. Pamphila peekius Kirby. 



58. Amblyeertes eos. Edw. 



59. Amblyeertes via lis Edw. 



60. Pyrgus tessellata Scud. 



61. Nisioniades juvencdis Fab. 



62. Nisioniades brizo Bd-Leo. 

 (>:5. Nisioniades icelus Lintn. 

 64. Nisioniades martialis Scud. 

 (i^). Pholisora catullus Fab. 

 G6. Eudamus pi/lades Scud. 



67. Eadamus bathyllus Sm-Abb. 



68. Eudamus tityrus Fab. 



69. Eudamus lyddas Sm-Abb. 



No. XII. 



AQUATIC RESPIRATION IN THE MUSK-RAT. 



W. L. SPOON. 



During the winter of 1879-'80 I spent much of my time 

 trapping the musk-rat, and had rare opportunities for studying 

 their habits. I have frequently noticed an ingenious device, to 

 serve as an apparatus for aquatic respiration, resorted to by the 

 animal when driven from its burrow into a pond frozen over. 

 In attempting to cross the pond under the ice, if the pond is too 

 wide for the musk-rat to "hold its breath" until it reaches the 

 opposite shore, it will stop for a few moments, exhale the air, 

 which is held down by the ice. Interchange of gases takes 

 place between the air and water, when the animal re-breathes 

 the air and makes another start, repeating the act until the shore 

 is reached. 



I do not claim this as an original observation. Others than 

 myself have noticed it. It is well known by those who have 



