g2 BOARD OF AGRICULTURE. 



Sub-class Tkleostei. Gastebosteoid^. 



ate between the fourth gill and inferior pharyngeal bones, is fully 

 developed. 



Fins. — The spinous rays of the dorsal region, instead of being 

 united by a membrane into a dorsal fin, are isolated from each 

 other. Each spine has a very small membrane at its posterior base. 

 Spines variable in number, transversely flattened upon their base, 

 and acerated upon their extremities, either smooth upon their edges 

 or denticulated. Can be laid back in a horizontal position. Ven- 

 tral fins situate about the middle of the abdomen, composed almost 

 exclusively, with few exceptions, of one stout spine. 



Pelvic bones are external and united to the thoracic belt. 



Genus Gasterosteus, Artedi. 



Gen. Chae. Uppci- surface of head plane either smooth or corrugated. Oper- 

 cular apparatus without spines. Mouth rather small, oblique ; posterior extremity 

 of maxillary not extending as far as a vertical line drawn in advance of the anterior 

 rim of the orbit. 



Minute velvet-like teeth upon the dentaries and premaxillaries ; none on either 

 the vomer or the palatines. Gill openings separated by a narrow isthmus ; branch- 

 iostegal rays three on either side. First dorsal represented by a series of isolated 

 spines, varying in number. Caudal fin subtruncated, or subcrescentic posteriorly. 

 Insertion of ventrals situate opposite the second dorsal spine, therefore abdominal ; 

 has one strong spine. Body either covered with a smooth skin, or partly, or totally 

 covered with tranversely elongated plates. Lateral line very obsolete. Bones of 

 the pelvis forming a shield to the belly, pointed behind. — Grd. 



Gasterosteus biaculeatus, Mitch. 

 Two-spined Stickleback. 



The stickleback is among fishes what the Bantam is among poul- 

 try — small, active, smart and pugnacious — often attacking and 

 driving much larger fishes than themselves. 



This little species is found in the small pools and creeks in many 

 parts of the seashore and in salt marshes. It is characterized by 

 two distinct spines on the back and a third near the dorsal ; a strong 

 serrated spine on each side, representing the ventrals. 



The head is somewhat depressed or flattened above, with numer- 

 ous punctures in rows, or as it is said by some, to be granulated ; 

 jaws equal ; teeth minute and numerous. Eyes large for the size 

 of the fish — pupils black, iris silvery. Opercles of a silvery color, 

 spotted with dusky, covered with stri». Mouth protractile. Nos- 



