SECTION XIL 255 



ftrufture, or appendices^ as he calls it, of 

 one kind, PL XX. fig, a. 



He alfo gives other figures in the faid 

 plate, but two of them, viz. D. and E. 

 are not teftaceous animals. He defcribes 

 them, p. 3ii> & feq. in the following 

 manner ; the hinge of the under valve i& 

 compofed of two fmall hooks, which are 

 taken in or hinged into the finufes or ca- 

 vities of the upper valve, and it has twa 

 interior appendages fixed towards the top 

 of the upper valve : this (Irufture he ob- 

 ferved in two fpecies. In another fpecies^ 

 the hinge w^as nearly the fame, but had 

 two long and narrow fide appendages pro- 

 x:eeding from the top of the upper valve^ 

 which extend themfelves to the middle of 

 It, where they are bound or flopped by 

 two fmall ligaments, and then return again 

 towards the top, in a very remarkable and 

 curious manner, PI. VI. fig. 7. And a 

 third fart, (w^hich is that of Gualtieri), 



has an interior appendage like to a per- 

 pendicular 



