258 ON THE CLASSES OF THE 



loner thin piece of horn, analogous to nothing known in 

 the true Mollusca. In the genus Octopus we have the 

 first indistinct trace of it in two small conical grains of a 

 horny substance placed in the thickness of the back. 



From the abovementioned two envelopes, therefore, 

 which in a true Cuttlefish form a cartilaginous or coriaceous 

 sack, but in the type of the Chelonian reptiles are bony, pro- 

 ceed in both tribes of animals a neck, head, and scull; for, 

 as has been already noticed, a very distinct vestige of a scull 

 may be seen in the Cephalopoda. The mode in which the 

 species are reproduced is also in these last animals said to be 

 similar to the known method of the Batracian reptiles. The 

 eggs of the Calymary and of the Cephalopoda in general are 

 united into small masses by a gelatinous substance similar to 

 those of certain Reptiles ; and the circumstance, mentioned 

 by Cuvier, of the vitellus hanging to the body of a young 

 Cuttlefish by a pedicle, is still analogous to what is observa- 

 ble in Birds and Tortoises. It may therefore be concluded 

 with safety that the Cephalopoda come nearer to Reptiles 

 than to any other vertebrated animals, and that of the Rep- 

 tiles they come nearest to the Chelonians. The hiatus that 

 occurs between them is indeed vast, and hardly requires to 

 be mentioned, since its existence is sufficiently demonstrated 

 by the circumstance that hitherio no person has thought of 

 the affinity. Still there is nothing yet to warrant the bold 

 assertions that the Cephalopoda are in their construction in- 

 sulated beings " leading to nothing," that they are entirely 

 different from the Vertebrata, and that here Nature has 

 evidently made a saltus. Such doctrines can only be 

 listened to when the bosom of the deep, and the vast tracts 

 of land which remain, to the peculiar disgrace of England, 

 still unexplored by the naturalist, shall have delivered up 



