348 FOSSILS FROM THE 



—destined to perform so important a part in the animal eo- 

 nomy, — presenting in this early age its distinguishing cha- 

 racteristics ; in especial, those numerous life-points from 

 which its organization begins, and which istill remain open, as 

 the sheltering cells in which vitality should reside. Was it 

 impossible in the nature of things that life should be equal- 

 ly diffused over hard and rigid earth, built up into this new 

 animal substance, bone 1 and was it therefore merely thick- 

 ly sown over it in hollow microscopic points ? Is bone a 

 thing rather strongly garrisoned by vitality, than itself vital f 

 There are laid on the table, among the other Old Red Sand- 

 stone fossils, specimens of a well-marked though doubtfully in- 

 terpreted bone, which, in all the osseous fishes, and in almost 

 all the ganoids, forms the largest and most important part of 

 the scapular belt or ring. [Spec. 27.] In common parlance, 

 and at our tables, it bears the name of the shoulder-bone, — 

 a name, however, which properly belongs to the much smaller 

 bone attached to it above by a squamose joining, and which 

 is similarly attached, in turn, to the forked super-scapular bone 

 which fixes the scapular belt to the head. This massy bone, 

 — in most of the osseous fishes one of the largest which oc- 

 curs in the skeleton, — whether we regard it, with Professor 

 Owen, as coracoidan, or, with Mr James Wilson, as the 

 humerus, or leave, with Agassiz, its homologues undeter- 

 mined, — is evidently of great importance in the ichthyic 

 economy, as at once furnishing a base to the pectorals, a 

 strencfthening belt to the abdomen, like that furnished in the 

 higher animals by the bones of the breast and sides, and as 

 supplying, yet further, a firm, unyielding basement on which 

 the gill-covers may fit tightly down. In all our existing 

 placoids of the shark type, if we except the genus chimsera, 

 which does not appear in geologic history until after the com- 

 mencement of the Secondary ages, the scapular arch is placed, 

 as in birds and mammals, at a considerable distance from the 



