Geology of England and ffales,'^'' fyc. 235 



their recesses : we must remember that we were long ac- 

 quainted with the encriniteSi.,in a fossil state, before the an- 

 alogous beings in a recent state had found their way to our 

 collections ; yet the general facts seem too strong to be en- 

 tirely thus accounted for. With the exception of those 

 contained in the most recent beds (the crag) oiily, nine out 

 often fossil shells belong to species decidedly different 

 from any known to exist. The family of ammonites, for 

 instance, contains more than 200 fossil species occording 

 to many authors, and it does not seem possible to reduce 

 the estimate above one half; yet of all these not one is 

 known recent, and the only recent species of the whole 

 genus is a very minute shell ; yet the fossil species some- 

 times measure three feet iiv diameter. Is it probable that 

 a genus so numerous, and having species of such large size, 

 can have been overlooked, especially as they are furnish- 

 ed with an apparatus whose use was evidently to give them 

 buoyancy, like the allied family, the nautilus? so that it is 

 not likely they can remain concealed from inhabiting deep 

 waters only. The same remarks will apply to tlie belem- 

 nites, of which no recent species is known." 



"The remains of marine oviparous quadrupeds (Ichthy- 

 osaurus, Plesiosaurus, Maestricht animal, &:c.) are refera- 

 ble to new genera widely different from any thing with 

 which we are acquainteo, and the fossil species of croco- 

 dile are strongly distinguished from the recent- These en- 

 ormous and singular animals (sometimes almost rivalling 

 the whale in size) which must often come to the surface to 

 breathe, cannot surely have eluded the observation of all 

 our voyagers. The land quadrupeds found in some of the 

 most recent strata, and many of those even mingled in the 

 diluvial detritus with the bones of animals still existing in 

 the same countries, are often of genera widely distinct from 

 any with which we are acquainted (e. g. Palseotherium, 

 Megatherium, Mastodon, ^c.) or of distinct species, as the 

 fossil bear, rhinoceros, and elephant j and M. Cuvier has 

 shown at large the little probability there is that any of 

 them exist in an unknown condition. It must be carefully 

 remembered that an accurate and rigorous knowledge of 

 Zoology is requisite in any on*- v\ho ventures to discuss 

 this subject ; a superficial acquaintance with it can only 

 lead into confusion and error." p. 9. Introd. 



