A DAY IN A QUARRY. 95 



"A trilobite? I think I have heard of that 

 creature before." 



' I dare say yon have. It is often referred to in 

 discussions on Design and Evolution. Trilobites 

 belong to the same animal group (Crustacea) as 

 the lobster. They are found in works far older 

 than even these ancient Wenlock strata ; indeed, 

 they are amongst the oldest inhabitants of our globe. 

 Although they became extinct many ages ago, for 

 they do not occur in any rocks newer than the 

 Carboniferous, yet so perfectly have they been pre- 

 served, and in such vast numbers, that it is possible 

 to study their structure, even to the minutest detail, 

 from their fossil remains. Their external covering 

 is divided into three lobes, and it is this feature 

 which has originated their name ; for trilobite, as 

 you know, means three-lobed. They vary greatly 

 in size, some, like the Olenus, being as small as a 

 pea, and others attaining to a length of several 

 feet. These interesting creatures can be traced 

 through about twenty metamorphic stages. Dr. 

 Buckland, in his famous " Bridgewater Treatise," 

 pointed out that the same modification of the 

 organ of vision is found in this earliest Crustacean 

 as in some living representatives of this group; hence, 

 the mutual relations between light and the eye 

 must have been the same in those remote ages as 

 at the present day. Any argument for the doc- 

 trine of Evolution, therefore, which is based on 

 a supposed change of environment since those 

 primeval ages, is certainly weakened by the evidence 

 which the trilobite's eye furnishes. The trilobite, 



