No. 5.] NATURAL HISTORY SOCIETY. 289 



P5'gidium, and the greatest number ot thoracic segments. Indeed 

 there are forms to represent almost every stage, and there can I think 

 be no doubt that in the fauna of the Tremadoc group, which is sepa- 

 rated from the earlier Cambrian by several thousand feet of deposits 

 indicating a period of very shallow water in which large brachiopods 

 and phyllopod crustaceans were the prevailing forms of life, we wit- 

 ness a return to very much the same conditions as existed in the 

 earlier Cambrian periods, and with these conditions a fauna retaining 

 a marked likeness to the earlier one, and in which the earlier types 

 are almost reproduced, though of course greatly changed during their 

 previous migrations. The Niobe(?) recently found in the Tremadoc 

 rocks is truly a degraded Paradoxldes^ retaining the glabella and head 

 spines, but with the rings of the thorax, excepting eight, consolidated 

 together to torm an enormous tail. Instead therefore of liaving here^ 

 as stated by M. Barrande, "a very important discord between Dar- 

 winism and facts," we find in these early faunas facts strongly favour- 

 ing such a theory, and in support of evolution. 



This is an exquisite piece of evolutionist reasoning, worthy 

 of some of the greater masters of this peculiar logic. It i» 

 assumed that specific diiFereoces are "gradations" and the 

 word "■ almost " covers the gaps between these. It is taken 

 for granted that Paradoxides, which disappears with the Mene- 

 vian age, has only gone upon its travels to parts unknown, and 

 after the deposition of several thousand feet of beds, returns 

 disguised as the Niobe of the Tremadoc, — and not only changed 

 but " degraded ", — a sorry result certainly of the struggle for 

 existence in the interval, and holding out small prospect that the 

 creature can be promoted in any subsequent age into a fish or 

 even into a Decapod. If Barrande's reasoning can be met only 

 in this way, he need not fear for the result. Seriously, one 

 scarcely knows whether to be amused or grieved at the phases 

 which the doctrine of derivation assumes in the writings of some 

 modern naturalists. It is at least devoutly to be hoped, in order 

 that science may not fall under tiie contempt of all thirikino- men, 

 that the advocates of tiiis hypothesis may become more careful 

 in their treatment of facts, and more modest in their demands on 

 our faith. 



In the meantime the record of the rocks is decidedly against 

 them in the particular point to which I have above adverted, 

 namely, the abrupt appearance of new forms under several specific 

 types and without apparent predecessors. They should direct 

 their attention in this connection to the appearance of Foramin- 

 ifera in the Laurentian, of Sponges^ Brachiopods, Trilobites^ 

 'V'oL. 7. T No. 5. 



