ZOOLOGY. 299 



over a fall of forty feet, so that the fish can ascend without difficulty. 

 This river, which a few years ago was entirely barren, now abounds 

 in salmon to such an extent that in the month of July, 1862, as many 

 as one thousand salmon were captured at one locality in one week. 



Acclimatization of Sponges, The French government, encouraged 

 by the success which has attended themefforts in pisciculture, are now 

 attempting to introduce the artificial growth of the finer and more 

 valuable sponges. It is now universally acknowledged that sponges 

 belong; to the animal kingdom, and are an aggregate of cellules built 

 up by~a gelatinous polyp similar to those which construct madreporae, 

 porites, and other polypifers. When the sponge is first gathered at 

 the bottom of the sea, it is covered with a black but transparent gela- 

 tinous substance, resembling vegetable granulations, among which 

 microscopic white and oviform bodies may be distinguished. These 

 are the larvae destined to perpetuate the species. When arrived at 

 maturity, they are washed out by the sea-water which incessantly 

 flows through the sponge ; they then swim along, by the aid of the 

 vibrating cilia or hairs with which they are provided, until they reach 

 a suitable rock, to which they attach themselves, and there commence 

 a new life. This emigration of the larvse, from the parent sponge 

 occurs about the end of June and beginning of July. The French 

 authorities collected the sponges on the coast of Syria, before the per- 

 fection of the larvaa, and, transporting them to proper localities on the 

 coast, of France, sunk them, arranged in stone troughs. The success 

 of the experiment cannot, of course, be known at present. 



Oyster-Breeding. M. Coste, who has long paid great attention to 

 pisciculture in all its branches, has recently made a very interesting 

 report to the French Academy " On the Condition of the Artificial 

 Oyster-beds on the West Coast of France." The principal locality 

 selected for the operations is the shore around the Isle of Re. This 

 island, which is sixteen miles long and four broad, is very favorably 

 situated for the breeding of oysters. The sea-bottom fringing the 

 island was cleared from all impurities ; and the seed from oysters hav- 

 ing been strewn on the bottom, the work of reproduction went on. 

 Now, it is calculated that seventy-two millions of oysters are pro- 

 duced annually, which, at the rate of 25 or 30 francs per thousand, 

 amounts to two millions of francs per annum. M. Coste states that 

 nothing but very violent currents and a bad sea-bottom prevent the 

 oysters from breeding. 



The Smallest of Vertebrate Animals. Dr. G. C. Wallich has recent- 

 ly contributed to the Annals of Natural History, London, a drawing of 

 a lower jaw, the extreme length of which is the 100th of an inch. 

 Assuming the body to have been five times as long as the jaw, he 

 says, " Here we have evidence of the existence of a vertebrate ani- 

 mal measuring only the 20th of an inch, a size considerably below 

 many of the organisms usually regarded as microscopic. The jaw 

 was recently detected on a shell containing a specimen of muddy 

 deposit dredged up at St. Helena in 1857, in thirty fathoms of water." 



Connection between Human and Cattle Disorders. Prof. Gavngee, 

 in an article on the " Health of Stock," in the Edinburgh Veterinary 

 Review, states that he has noticed a remarkable connection between 

 diseases in man and in the lower animals ; he believes many of the for- 



