304 ANNUAL RECORD OF SCIENCE AND INDUSTRY. . 



the Fiilix marila^ or black-headed duck (shuffler), a species 

 well known to sportsmen and naturalists as common to both 

 Europe and America. This identification, if correct, of which 

 Mr. Van Beneden seems to entertain no doubt, is an inter- 

 esting fact, as carrying back this species through a very re- 

 mote antiquity. The remains discovered consisted of a com- 

 plete sternum, a large portion of the skull, the clavicle, hu- 

 merus, and other portions of the skeleton. Bull. Acad. Hoy. 

 des Sciences, Bruxelles, 1873, 354. 



RESPIRATION IN FISHES AT DIFFERENT AGES. 



A series of experiments lately made by Quinquand, and 

 announced to the Academy of Sciences in Paris, will be of 

 much importance in the practical question of the culture of 

 young fish, and their transportation in small bulk and in a 

 limited quantity of water from one point to another. Accord- 

 ing to this author, the amount of oxygen consumed by the 

 same fish is in proportion to the time twice as much being- 

 required in two hours as in one. The relative power of res- 

 piration, however, in fish diminishes with the increase in 

 weight; as a carp of three and a half pounds consumes, in 

 proportion, scarcely more than one fourth as much as one of 

 three fourths of an ounce in the same space of time. There 

 appears to be comparatively little variation in the amount 

 of oxygen required in the same time by different species of 

 fish of the same weight. In fish weighing less than one 

 pound, the activity of respiration is considerably greater in 

 proportion than in those that are heavier. Carp weighing 

 from one to two pounds consume from one seventh to one 

 ninth as much oxygen as man in the same time, and of the 

 same unit of weight of living matter. Tench weighing over 

 one i^ound have a respiratory activity one ninth as much as 

 man. As already stated, the activity of respiration is greater 

 in fish of small size. Thus a tench of four and a half ounces 

 only consumes two ninths as much oxygen as man in propor- 

 tion to the weight ; while one a little less than an ounce re- 

 quires half as much. It is known that among mammals the 

 new born young resist asphyxia much more vigorously than 

 adults. The contrary seems to be the case among fishes. 

 Thus eels weighing one hundred and fifty grains perished 

 twenty-four hours sooner than others of six hundred grains 



