FOSSILS OF OLD RED SANDSTONE. 51 



see the form of those organs among the sauria. 

 It appears, in short, according to this writer, that 

 the fiirther back we go among the fishes, we find 

 them possessed of the higher characters. Of the 

 real character of all this hardy assertion I shall 

 enable the reader to judge. The fishes of this 

 early age, and of all other ages previous to the 

 chalk, are for the most part cartilaginous. The 

 cartilaginous fishes — Chondropterigii of Cuvier — 

 are placed by that naturalist as a second series in 

 his descending scale ; being, however, he says, " in 

 ome mesLSure parallel to thefirstP How far this 

 is different firom their being the highest types of 

 the fish class, need not be largely insisted on. 

 Linnaeus, again, was so impressed by the low 

 characters of many of this order, that he actually 

 ranked them with the worms.* Some of the car- 

 tilaginous fishes, nevertheless,have certain peculiar 

 features of organization, chiefly connected with 

 reproduction, in which they excel other fish ; but 

 such featiures are partly partaken of by families in 

 inferior sub-kingdoms, showing that they cannot 



* Dr. Fletcher places the Chondropterigii lowest in a scale 

 ■which takes as its criterion " an increase in the number and ex- 

 tent of the manifestations of life, or of the relations which an 

 organized being bears to the external world." 



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