77 



CHAPTER XIY. 



KELLADI^, SPECIES AND HABITS ; MONTACUTA, TURTONIA, KELLIA, GALE- 

 OMMA, LEPTON. — OBSERVATIONS ON A LIVING CAPTIVE. — CYCLADID^, 

 CYCLAS AND PISIDIUM. 



KELLADI^ AND CTCLADID^. 



Although compelled by our limits to pass quickly over the 

 little creatures composing these two groups^, they are by no 

 means without interest. This is saying no more than might 

 be said of the smallest thing that has life ; but we shall find 

 among these tiny shell-fish instances of beauty in form and 

 nicety of adaptation. 



The Kelladi^ are marine, and have only one siphonal 

 opening ; their foot has a little groove, in which is inserted 

 a little hairy byssus; the valves of the shell are thin and 

 oval. 



I. MoNTACUTA has no tubes_, only one opening, a large 

 triangular-pointed foot, exserted forwards. The light, thin 



