180 EVIDENCE OP THE SILURIAN MOLLUSCS- 



eight species, and the Brachiopods at one hundred and fifty ; 

 whereas at the same date there were two hundred and five 

 Cephalopods of the Oolitic formations enumerated, and but 

 fifty-four Brachiopods. It is the molluscs of the inferior, not 

 those of the superior class, that constitute (with their contem- 

 poraries the Trilobites) the characteristic fossils of the Silu- 

 rian rocks ; and hence the propriety of the distinctive name 

 suggested by Sir Charles Lyell. But in the development 

 question, what we have specially to consider is, not the num- 

 bers of the low, but the standing of the high. A country may 

 be distinctively a country of flocks and herds, or a country of 

 the carnivorous mammalia, or, like New South Wales or the 

 Galapagos, a country of marsupial animals or of reptiles. Its 

 human inhabitants may be merely a few hunters or shepherds, 

 too inconsiderable in numbers, and too much like their breth- 

 ren elsewhere, to give it any peculiar standing as a home of 

 men. But in estimating the highest point in the scale to 

 which the animal kingdom has attained within its limits, it 

 is of its few men, not of its many beasts, that we must take 

 note. And the point to be specially decided regarding the 

 organisms of the Silurian system, in this question, is, not the 

 proportion in number which the lower forms bore to the 

 higher, but the exact rank which the higher bore in the scale 

 of existence. Did the system furnish but a single Cephalopod 

 or a single fish, we would have as certainly to determine 

 that the chain of being reached as high as the Cephalopod or 

 the fish, as if the remains of these creatures constituted its 

 most abundant fossils. The chain of animal life reached quite 

 as high on the evening of the sixth day of creation, when the 

 human family was restricted to a single pair, as it does now, 

 when our statists reckon up by millions the inhabitants of the 

 greater capitals of the world ; and the special pleader who, in 

 asserting the contrary, would insist on determining the point, 

 not by the rank of the men of Eden, but by the number of 



