Hinges of Britj/J} Bivalve Shells, 173 



(b) The correfponding depreflion. (c) A fmall tooth 

 on one fide of it. 

 Fig. 3,4. The hinge of the Mya^/mwrw. (a)The great tooth. (b)A 

 ridge grooved longitudinally, (c) A fmall curve in the 

 margin, (d) The cavity for the reception of the tooth. 

 5, 6. The hinge of the Mya margarittfera. (a) The rugged tooth, 

 (b) Its cavity, (c) A fharp ridge on one fide of it, 

 which pafles into the cavity (d). 



7. The hinge of the Mya plBorum. (a. a) The indented- 



teeth, (b.b) The remote teeth. 



8. A fide view of one valve of the fame. 



9. The hinge of the Solen Siliqua, 



10. The hinge of the S. Vagina. 



11. S. pellucidus. (a) The bifurcated tooth, (b.b) The two 



other teeth in the fame valve, ^c) The two oppofite 

 teeth. 



Tab. XV. 



1,2. The hinge of the Tellina planata. 



3, 4. The fame magnified*, (a, a) The large tooth in each 

 valve, (b.b) Two fmall teeth, (c) The lateral tooth. 



5, 6. The hinge of the Tellina incarnata. 



7, 8. The fame magnified. (a.a)The two large teeth. {b.b)The 

 two fmaller ones. Wl.cn the (hell is placed horizon- 

 tally thefe teeth appear very prominent, and the 

 fulcus in the lars^e tooth is very apparent. 

 9, 10. The hinge of the Tellina cornea. 



* The fliells were, fcr the moft part, magnified by Ellis's fingle Aquatic Microfcope. 



Fig. 



