CIIOXDROPTERYGII BRAXCIIIIS LIBERIS. 331 



regular. The first dorsal, containing a strong spine, is placed over tlie pectorals ; and the males, as in 

 tjic Sharks, have a bony appendage to tlie ventrals ; but these are divided into three branches, and they 

 have S]iinous appendages l)efore tlie base of the ventrals, and small spines on the point of a fleshy 

 appendage between the eyes. Tlieir eggs are large and flattened, with a leathery covering, and 

 having margins. [In fact, with some suignlar peculiarities, they approach pretty closely to the fishes 

 with fixed gills.] 



C. monstrosa, tlie King; of the Herrings, and Cat of the Meilitorraiiean, is three feet long, .and of a silvery 

 colour spotted witli brov\n. It inhabits the liuropeaii seas, the northerly ones most abundantly. Another, funning, 

 pei-haps, a second subgenus, Callirlnjnclius, lias the snout ending in a fleshy appendage like a toe. The 

 second dorsal begins over the ventrals, and terminates at the comniencement of the fin under the tad. Cidy 

 one species, from the Suuth Seas, is known. 



THE SECOND ORDER OF CIIONDROPTERYGII. 



CHtlNDROPTERYGir BRANCHIIS FIXIS. 



Tlit'so have their gills attached at the outer edge, with a separate opening, through which 

 the ^^'ater from each gill escapes. They h.ave also small arches of cartilage suspended iu their 

 muscles, opposite the gills, which may be called giU-ribs. They form two families. 



THE FIRST F.UIILY OF THE CIIONDROPTERYGII BRANCHIIS FIXIS,— 

 Sici.ACHii (the Sharks and Ravn), — 

 AVhich has been comprised in two genera, has many common characters. The palatals and postmandi- 

 hnlaries arc ahme armed with teeth, snpjilying the place of jaws, the usual bones of whicli are mere 

 rudiments, a single bone reiircsenting tlie tympanal, jngal, and tein]>oral l)ones, and tlte preopercidum. 

 The OS 7i>/oldes is attached to this [)ediele, and supports gill-rays as in ordinary fishes, although not 

 distinctly visible externally. It is followed by branchial arches, but has none of the three pieces which 

 cmn})Ose the gill-lid. Tliey have pectorals and ventrals, the latter behind the abdomen on each side of 

 the vent. Their membranous labyrinth is inclosed in the cartilage of the cranium, and their cavities 

 contain starchy masses and not stony ones. The pancreas is a conglomerate gland, and not divided 

 into cocca ; the intestinal canal is short, but with a spiral valve. The se.ves pair regularly, the females 

 having oviducts highly organized, which supply the place of a matrix in those that bring both their 

 young alive ; such as produce eggs have them with a horny covering, the substance of wdiich is supplied 

 by a larger gland surrounding the oviduct. The males are casdy known by large appendages on the 

 inner edge of the ventrals, the use of which is not well known, [though Ijeheved to serve as clas-pers']. 

 Squnlus, the Sharks properly so called, have a long body ; a thick, fleshy tail; modi rate jiectorals ; 

 and resemble ordinary fishes in their form, having the gill-openings on the sides of the neck, not 

 below, as in the Rays, and the eyes in the sides of the head. The snout is supported by three carti- 

 laginous branches arising from the fore part of the cranium, and the rudiments of mamillaries, inter- 

 maxdlaries, and premandibulars, may be traced in the skeleton. The hone of the shoulder is sus- 

 pended in the muscles behind the gills, without connexion with the cranium or the spinal column. 

 Some are viviparous ; others produce eggs covered with yellow and transparent horn, of an oblong 

 shape, and with cords of horn at the angles. Tlieir small gill-ribs are apparent, and small ones are 

 traceable along the spine; their flob is dry and leathery, and eaten only by tlie poor. They are 

 ninneriius, and finni many subgenera. 



SciiUiiun (culled Dog-fishes on the British coast). — Snout blunt and short ; nostrils near the mouth, continued in 

 a groove to the edge of the lip, and more or less closed by membranes; teeth with a long point in the middle, and 

 a shorter one at eacli side. They all have spiracles, and one atual fin ; the dorsals are far backward, the first being 

 even tiel'ore the ventrals ; their caudal is long and truncated, and their gill-openings under the pectorals in the 

 British ones ; the anal is against the interval between the two dorsal.. The species are : 



S. canicf/ltT, the Small-spotted Dog-fish, with numerous spots an 1 the \entrals truncated.— .S". cutiUsy the Large- 

 spotted Dog-fish, with the spots larger, sometimes ocellated, and the ventrals square.— .S'. melastomum, Black- 



