PISCES. 



81 



were prepared, and sketch models made at a fraction of the natural size, and sub- 

 mitted to the above high authority. Clay models were then made of the natural 

 size. 



To give an idea of these monster Saurians, Mr. Hawkins states that the 

 Iguanodon, as it now stands in the Crystal Palace, is composed of four iron col- 

 umns, 9 feet long by 7 inches in diameter, 000 bricks, 1550 tiles, 38 casks of cement, 

 90 casks of broken stone, with 100 feet of iron hooping and 20 feet of cubic inch 

 bar. It was modelled after the great Horsham specimen : and the mold was af- 

 terward converted, into a salle a manger, in which Prof. Owen, Prof. Forbes, and 

 twenty other scientific gentlemen sat down to dinner. These beautiful restora- 

 tions are faithful copies, in miniature, of the gigantic group in London. 

 They are in five pieces : 



Ichthyosaurus with Plesiosauri : Size, 22 x 14. Price, $10.00 

 Megaxosaurus : Size, 23x12. Price, $7.00 



Iguanodon : Size, 19 x 14. Price, $5.00 



Labykinthodon : Size, 13x8. Price, $5.00 



Ptekodactyle : Size, 9x9. Price, $5.00 



Price of the set, $30.00 



CLASS IV.— PISCES. 



This Class is the most heterogeneous among Vertebrates. No an- 

 imals, indeed, exhibit such extraordinary aberration of form or assume 

 such peculiar shapes. They are every way inferior to the other mem- 

 bers of the sub-kingdom, — falling behind in strength and compactness 

 of structure, in intelligence and sensibility. They readily separate into 

 the Osseous and Cartilaginous. The former include the common Fishes 

 or Teleosts, and rank lower than the Cartilaginous ; they are, neverthe- 

 less, the typical forms, and are the most numerous. 



Over fifteen hundred fossil species have been described. Sedi- 

 mentary strata, composed of fine detritus, have been most favorable for 

 the preservation of entire forms; but in coarse limestone and conglom- 

 erate, the principal vestiges are detached teeth, scales and bones. The 

 Fishes of the older formations differ most from existing species ; the 

 pectoral fins are smaller and invariably placed before the ventral. Above 

 the Chalk, the ventrals approach nearer the head. The earliest evi- 

 dences of a fossil vertebrate are the dorsal spine of a Shark and a 

 buckler like that of a Placoganoid, both found in the Upper Ludlow by 

 Murchison. (A Pterasjns Ludensis has since been discovered in the 

 Lower Ludlow of Herefordshire, England, 1859.) We may infer the' 

 co-existence of some more powerful predatory Fish against wliose 

 6 



