338 ANNUAL OF SCIENTIFIC DISCOVERY. 



the mouth with the food of the .animal, the water in the nasal cavities, 

 and the secretions of the bronchial tubes. As it appears in the form 

 {of a sudden discharge of vapor, he thought a fourth explanation might 

 |be added, the sudden rarefaction of the air when inhaled, followed by 

 a sudden condensation when emitted. He thought it was partly due 

 also to the small quantity of water which entered the outer extremity 

 of the nasal passages. He had succeeded in imitating the appearance 

 in question, by introducing a small quantity of water into the end of a 

 syringe and suddenly expelling it, with the body of air behind it, with 

 considerable force. 



Dr. Pickering said he could not think the condensation of the air 

 when expelled from the lungs of a whale was a circumstance of mucli 

 importance in forming the jet, as in tropical climates, where this could 

 hardly occur, the jet was as complete as in colder latitudes. 



Dr. Wyman said, that in some instances he had heard the inspira- 

 tion, as well as the expiration, of Cetaceans. It follows the expiration 

 instantaneously, but is much shorter and less audible. 



Mr. Ayres, from his own observations, confirmed Dr. Wyman's 

 views. He had noticed in a young porpoise that the act of breathing 

 is much more slowly performed than in the adult. 



BRAIN IN ARTICULATED ANIMALS. 



M. FELIX DUJARDIN concludes, from observations made upon numer- 

 ous species, that there exists in certain articulated animals a true 

 brain, the structure and size of which correspond to the development 

 of the intellectual faculties. It consists of well-marked symmetric 

 brains complex in form, and of pedunculated bodies surrounded by a 

 pulpy cortical substance, the more abundant in proportion as the in- 

 stinct tends to predominate over the intellect. The peduncle is ter- 

 minated above by radiated disks, and below divides into two tuber- 

 cles, the one of which seems intended to communicate with the other 

 half of the brain. The pulpy substance exists only in those insects in 

 which instinct alone can be distinguished, and it alone constitutes the 

 nervous ganglions of the chest and stomach, which preside over pure- 

 ly instinctive acts. The pedunculated bodies are the more developed 

 in proportion as the intellect predominates over instinct ; thus, in the 

 bee, they form a fifth of the volume of the brain, and the nine hun- 

 dred and fortieth part of the whole body, while in the beetle they do 

 not equal a thirty-three thousandth. Paris Correspondent of the 

 Courier des Etats Unis. 



BLIND ANIMALS OF THE MAMMOTH CAVE OF KENTUCKY. 



PROF. WYMAN gave an account of dissections of some of the blind 

 animals from the Mammoth Cave, Kentucky. In examining the 

 fishes, his results were the same as Miiller's, who found rudiments of 

 eyes, or black points of pigment, but no cornea, no optic nerve, no 

 ocular contents ; as the small filaments of the fifth pair of nerves 

 could be distinguished, he is confident the optic nerve could not have 



