228 



THE GEOLOGIST. 



wise"slio\\-ii tliat tlie valyes of Lingnla, when dried at 100 degrees, contain for 

 100^'parts 



Organic matter 45*20 



Carbonate of lime 6*68 



Phosphate of Ume 42*29 



Ditto magnesia 3*85 



Ditto sesqui-oxide of iron 1*98 



Silica traces 



This distinguished French chemist observes at the same time that this com- 

 position of the test of Lingula approximates to that which M. Chevrenil 

 signalized in the scales of the Lepidostria, as well as to the test of insects, as 

 described some years ago by Halchett. 



In the interior of the valves may be seen a number of muscular and other 

 impressions, with which the palseontologist should become acquainted ; but it 

 would be out of place were we to enter into a minute anatomical description of 



Fig. 1. Fig. 2. 



Lign. 9. — Lingula anatina (recent). 



Fig. 1.— Ventral Valve, Woodwaaxl, Hancock, etc. ; valve superieiu-e, Gratiolet. Fig. 2.— Dor- 

 sal valve, Woodward, Hancock, etc. ; valve inferiem-e, Gratiolet. 



J) (I, Posterior ooclusor, Hancock; = anterior adductors, Woodward; = pre-adductetu-s, Gra- 

 tiolet; = unicrc schiese mnskelbiindel, Vogt; = muscles qui vont directement d'une 

 coquille a rautre, C'uvier. a a, Anterior occlusor, Hancock; = anterior reti-actors, Wood- 

 word ; = ninscles ol)li(iucs postero-antorieurs, Gratiolet ; = mittlere schicse muskelbiindel, 

 Vogt. rrr, Divnricator, Hancock ; = posterior adductor, Woodward ; = post-adductem-s, 

 Gmtiolct; — obcrcr schlics^muskel, Vogt. pp. Posterior adjustor, Hancock ; = posterior 

 retractors, Woodward ; = muscles croise on oblique transverse, Gratiolet. e p, External 

 adjustor, Hnncock ; == extcnml protractors, Woodward ; = sui-face siu* la quelle se prolonge 

 rinsortion du muscle cibli(jue nntero-postoriem' paii"e externe, Gratiolet. c p and c' j^', Cen- 

 tral adjustor, Ilancoclc ; = central protractor. Woodward; c p, muscles obUques anterieurs 

 paire intenie, GviHii^k t ; nnd i>' , muscles obliques anteriem-s paire interne et externe, 

 Gratiolet. x. Line imlicatiru- the posterior parietals, Hancock; = peaussier verticaux, 

 (Trntiolet. 71, Pcdnuculnr uuisclc, Hancock; = capsule of pedicle, Woodward; = muscle 

 intcrieur du pcdouclc. G rat iolei . /. Impressions produced by the central branches of sinuses, 

 Hnncock. », Inqu-essions produced by the outer or lateral branches of smuses. v, Inipres- 

 .sions produced by paUial lobe. 



