5 Of the Barnacle. 



Circumference, as the Subftance 

 that conftitutes it is of a confiderable 

 Thicknefs, compofed cf feveral Mem- 

 branes inclofing each other, which con- 

 fift of longitudinal Fibres, capable, 

 while the Animal is alive, of being 

 extended to near twice its natural 

 Length, and when dry contra&s, 

 hardens, and is rough like Shagreen, 

 I imagined at firft this to be the 

 Cafe containing the Body of the Fifh, 

 but upon Examination find, that 

 the Shell, which tips the Extremity 

 of it, contains the whole, Fifh, with- 

 out any fenfible Opening into the 

 hollow cylindrical Stem, or permit- 

 ting the Animal to have any ap- 

 parent Communication with it; and 

 it is upon this Account that I term 

 it a Stem, and not Part of the Cafe, 

 as I formerly fuppofed it to be. 



late VI. The Shell containing the Fifh is 

 Fig. 2. a. to appearance bivalve, tho 1 upon an 

 accurate Inipection it appears that 

 each Side of it confifts of two Parts, 

 adhering together by a thin Mem- 

 brane lining the concave Surface, 

 which confequently goes between each 

 Divifion, and joins them to each 



other 



