CATECHISM OP CONCHQLOGY. 17 



A. The interstice which separates the valves 

 when the ligament is wanting, or the hollow 

 which is covered by the ligament. 



Q. What are the Squamulae ? 



A. Scales. 



Q. What the Strise? 



A. Elevated lines or furrows. 



Q. What are the Tulci ? 



A. They are sometimes used, though perhaps 

 improperly, to signify the same as Costae ribs. 



Q. Does not the word Testa signify a shell ? 



A. Undoubtedly. 



Q. What is meant by ^Equilateral, or Inae- 

 quilateral valvae or valves ? 



A. 1st. That the anterior and posterior side* 

 of the valves are equal. 2d. The reverse. 



Q. What is meant by dextra et sinistrce ? 



A. Right and left. 



B 3 



