406 ptsces. 



thin sharp-pointed teeth of the shark, hut much more so than the skate 

 has. 



The crystalline humour coagulated in the kingston fish's stomach; 

 therefore there is a coagulating property in the stomach of that fish. 

 The testicles of the shark, thornbaek, Kingston, and dog-fish, become 

 larger at the time of copulation, like the ovarium in the female 1 . 



On the inner and unconnected edge of the spiral valve of the gut of 

 a skate, &c, there is an elastic ligament running the whole length of 

 that edge, which always keeps it out of one length 2 . 



The Fire-flare [Trygon Pastinaca, Cuv.]. 

 A fish, called the fire-flare, is very much of the skate-kind ; only 

 darker on the hack, having the upright holes [spiracnla] close to the 

 eye, as it were, through the orbits. It was, anatomically, a skate. 

 The external characteristic of these fishes is the small mouth on the 

 under surface [of the head] ; five slits in the skin on each side, viz. the 

 openings for the gills ; and the holes [spiracula, ' evens '] leading from 

 the mouth to the upper part of the head. There are two flat fins by 

 the sides of the anus : the tail is a continuation of the body 3 . 



[Order Holocephali.] 



[The Southern Chimera (Callorhynchus antarcticus, Cuv. 4 ).] 

 It is to be observed that Nature has a certain number of modes of 

 performing every one of her actions, no two of which are alike ; and, in 

 a general way, she has united her various operations so as to form a 

 compound, which in the whole has a specific quality, and which union 

 constitutes a genus of a species. 



Each mode may be reckoned like a letter in the alphabet ; by uniting 

 them a word is produced ; and by diversifying them different words are 

 produced, only that words do not approach nearer in meaning by 

 having more of the same letters in them. If Nature was uniform in 

 this mode of union of her operations, then the Natural History of these 

 compounds woidd be more easily attained. It would be like a universal 

 language; and, in natural things, it would only be necessary to see 

 one part of any of the compound to judge of the whole 5 . But she appears 



1 [Hunt. Preps. Phys. Series, Nos. 2677, 2678.] 2 [lb. Nos. 650, 776.] 



3 [The tail, with the serrated spine, of a Trygon Pastinaca, form the specimen 

 No. 531 of the Hunterian Osteological Series. The organ of smell is preserved in 

 the Physiological Series, No. 1529.] 



4 [This article is headed " New Shark : " the description accords with the speci- 

 men No. 2676, Hunt. Phys. Series.] 



5 [Cuvier's ' Law of Correlation ; ' applicable, in certain well-defined and natural 

 groups, to palaeontology.] 



