24 



Part first. 



Fig. 64. T/ialassochelys corticata (Caouana), 

 y^ nat. size. p. 99. 



In front of tank 10 is a little open trough. Lying on or 

 half buried in the shingle is an Electric Ray {Torpedo, fig. 65) 

 from which shocks may be taken. The lingers should be pla- 

 ced under the broad part of the body, the thumb above, and 

 the animal squeezed or otherwise ill-treated. — Frequently 

 among the shingle are snmll white pointed objects, about two 

 inches long, looking not unlike split sardines. These are Lan- 

 celets {Amphioxus, fig. 60), the lowest Vertebrate, 



