276 NORTHERN ZOOLOGY. 



LOPHOBRANCHII. 



In this, the filth order of fish according to Cuvier's arrangement, the jaws, as in 

 the preceding orders, are complete and free ; but the branchiae, unlike those of 

 other fish, are divided into little round tufts disposed by pairs along the arches : 

 they are shut in by a large gill-cover bound down by a membrane, in which there 

 is merely a small hole for the exit of the water, and only vestiges of rays. The 

 Lophobranchii may also be known by their bodies being encased from one end to 

 the other by shields which give them, in almost every instance, an angular form. 

 They are generally of small size, and almost destitute of flesh. Their alimentary 

 canal is even, without cseca, and their air-bladder slender, but large enough in pro- 

 portion to the size of the fish. The order is divided into two genera, Syngnathus 

 and Pegasus, the species of the latter being inhabitants of the Indian Ocean. 

 Syngnathus is subdivided into three sub-genera, viz., the Sea-pipes, or True 

 syngnathi, the Sea-horses, or Hippocampi, and Solenostomus, of which the only 

 known species is an inhabitant of the Indian seas. Pennant mentions the Lesser 

 pipe-fish, or Syngnathus acus of Linnaeus, as belonging to North America, and 

 Drs. Mitchill and Smith include Syngnathus typhle in their lists of the New York 

 and Massachusetts fish. The peculiarity of the syngnathi carrying their roe after 

 impregnation in little pouches under the belly or tail, which are cleft to give exit 

 to the young when they are hatched, has been long known to naturalists, but Mr. 

 Yarrell has recently shown that it is the male fish alone which is provided with 

 these receptacles for the roe. 





