General Notes. [October, 



during mild winters both summer and winter eggs 

 and the successive broods of young after producing agamic 

 young, throw off an ephippium so that the pool is filled with eggs 

 which are calculated to stand any vicissitude. Thus it happens 

 that after a pond has been dried for a long time the first warm 

 shower quickens in it swarming life. The above facts are more 

 significant when we remember that the Cladocera are above all 

 others among Crustacea, the most useful as purifying agencies. 

 The greater number subsist entirely upon vegetable matter, and 

 the only means they have of collecting it is by causing a current 

 of water containing such minute particles as may exist in it to 

 pass between the rotating jaws, though, perhaps, in some cases the 

 labrum is sufficiently prehensile to grasp somewhat larger food. 

 Certain it is, however, that these same minute animals form an 

 indispensable agent in the economy of nature, purifying all our 

 stagnant pools of the decaying vegetation floating therein. One 

 who had given no attention to the number of these creatures 

 would undoubtedly be surprised on carefully examining a given 

 quantity of water from the nearest lake. Here are some figures. 

 In a quart of water taken by dipping from a lake near Minne- 

 apolis, the following were counted : 



Ceriodaphnia 14°° 



etc, all visible to the unassisted eye. — C. L. Herrick. 



On the Habits of Cryptobranchus. 1 — Living examples of 

 this Japanese salamander have rarely been brought to this 

 country, and the following observations may be worth recording 

 even if they merely confirm those of Hyrtl, Van der Hoeven and 

 others, whose works I have not yet had an opportunity to con- 

 sult. 



This specimen is about seventy-five centimeters (2^ ft.) long, 

 and was obtained for Cornell University through Professor H. 

 A. Ward, who brought it by hand from Japan. 



It is very sluggish, remaining quiet for hours in water, except- 

 ing for the respiratory movements presently to be described. 

 Nevertheless it can display considerable activity, and upon one 

 occasion escaped from a common wash-tub which was about 

 thirty centimeters (1 ft.) deep. Out of water it appears uncom- 

 fortable, and crawls first in one direction and then in another, 









