ZOOLOGY. 295 



Fren ;h Government to investigate and report on the expediency of 

 " Vh isections," or the dissection of animals alive, a plan of late years 

 much followed by French physiologists. The report of this commission 

 was read to the Academy of Sciences on the 4th of August. It arrives 

 at the following conclusions : 



" 1. Vivisection is indispensable to the study of physiology, and of 

 operative veterinary surgery. 



" 2. It ought, nevertheless, to be employed sparingly ,";and all appear- 

 ances of cruelty should be avoided. 



" 3. The experimenter should always have the real progress of sci- 

 ence in view. 



" 4. Students should not be permitted to perform vivisection except 

 in public, and in the presence of experienced professors. 



" 5. All means for alleviating pain compatible with the object in 

 view should be employed." 



Leaden Bullets injured by Insects. In 1857, the French Minister 

 of War sent to the Academy of Sciences several cartouches which had 

 been attacked in the wooden boxes in which they had been packed 

 by the larvae of insects of the order Hymenoptera. A similar fact has 

 recently occurred at Grenoble, where several of these insects have been 

 found with the deteriorated bullets in the cartouches. Specimens of 

 these also have been forwarded to the Academy by Marshal Valliant, 

 who is now united with the eminent naturalists, N Milne Edwards and 

 Quatrefages in a commission to inquire into the nature and labors of 

 these remarkable insects. 



Vocal Fishes. Dr. Dufosse has communicated to the French Acade- 

 my an account of certain researches into the vocal powers of certain 

 fish, most of his observations being made upon species of Trigla and 

 Zeus (gurnards and dories). He states the sounds to be produced by 

 the vibration of the muscles belonging to the air-bladder, and that large 



turnards may be heard at a distance of six or seven yards. Out of 

 ve or six hundred individuals, of the species mentioned, their voices 

 were comprised between sL and re b inclusive. The sounds were in- 

 stantaneous, or prolonged for several minutes, sometimes as long as 

 seven or eight minutes" The pitch often varies during a single " sono- 

 rous emission." The finest vocal performers appear to belong to the 

 species Morrude, who surpass all their congeners in producing a great 

 number of completely distinct sounds. " They sustain the simple sounds 

 better, and modulate better the compound sounds ; they render more 

 distinctlv long successions of sounds different in tone and pitch ; in fine, 

 there is less dissonance in the sonorous vibrations they produce. Other 

 species, however, beat them in intensity. 



The Rattle of the Rattlesnake. - - At a recent meeting of the Boston 

 Society of Natural History, Prof. Wyman made a communication on 

 the mode of formation of the rattle of the rattlesnake. 



In a foetal specimen examined, the scales cease toward the end of 

 the tail, and the unsealed portion is covered by thickened cuticle, the 

 rudiment of a rattle, which must fall off; as the animal grows, the last 

 three vertebras are covered with hardened cuticle arranged in ridges ; 

 as o-rowth continues, this covering is displaced, a new layer forming un- 

 derneath it, and the old slipped backward over one ridge in a manner 

 not well determined ; this is in turn displaced by a new layer beneath, 



