ZOOLOGY. 309 



watch in a dark room. At the expiration of about fifteen minutes 

 the light became gradually fainter, and in five or ten minutes more 

 had totally ceased. 



When sulphuric acid was dropped upon the water, it emitted for a 

 minute or two a bright light, and then disappeared. Nitric acid had 

 the same effect, and with hydrochloric acid the increased luminosity 

 Was much less conspicuous, and the darkness ensued almost instan- 

 taneously. A few drops of ether let fall into the sea-water in the 

 dark appeared instantly to deprive it of its luminous property. On 

 substituting chloroform for ether, in a second experiment, a very 

 bright and persistent phosphorescence was given out for a few min- 

 utes, after which the water speedily became dark, the animalcules 

 being evidently destroyed. 



FRESH-WATER COTTUS OF NORTH AMERICA. 



AMONG the papers presented to the American Association, in rela- 

 tion to the ichthyology of this country, we would mention a Mono- 

 graph of the Fresh-water Cottus of North America, by Charles Girard, 

 Esq., Cambridge, Mass. The investigations into which the author 

 has been led have shown that the C. gobio is not an inhabitant of our 

 country, as has hitherto been supposed, and that several other new spe- 

 cies of cottus exist in different hydrographic basins. 



NEW GENUS OF FISHES. 



THE Boston Journal of Natural History, Vol. VI. No. I., contains 

 a description of a new genus of fishes, established by Mr. W. O. 

 Ayres, of Boston, Mass. The specimen from which the description 

 is drawn was picked up at sea, in N. lat, 42, and W. Long, 50, 

 in the month of June, 1848. It was alive when taken, and was 

 floating in a vertical position, with a snout a little above the surface 

 of the water. It differs so widely from every established genus, that 

 even its place in the system becomes a matter of question. " It is 

 therefore necessary," says Mr. Ayres, " to form for its reception a 

 new genus, for which 1 propose the name Malacosteous, and which 

 may be thus characterized : 



" Mouth extremely deep cleft : border of the upper jaw formed principally by the maxil- 

 lary, the intermaxillary being short. Teeth in the upper jaw small, separate, and sharp- 

 pointed, on both maxillary and intermaxillary. Teeth in the lower jaw very long:, sepa- 

 rate, somewhat hooked, followed by others much smaller and closer together. No teeth on 

 the palatines, vomer, or branchial arches. A double row on the tongue. A single dorsal 

 fin near the tail, opposite the anal. Whole fish entirely destitute of scales. All of the 

 bones remarkably soft. Opercular pieces consisting of a membrane without ossification. 

 Branchial rays not discernible. The species, from its color, may receive the name Mala- 

 costcus niger." 



The length of the fish is eight and one half inches, with a body 

 nearly cylindrical. One of its most striking peculiarities is, that the 

 entire osseous system is in a very low state of development. All of 



