STUDY X. q81 



polit her eggs, is of a fhady colour ; thus the la- 

 mentine, which enters into the channel of the 

 rivers of America, in queft of food, in the verdure 

 of their banks, without leaving the water, de- 

 taches himfelf from that verdure, by the brown 

 colour of his fkin. 



The faxatile fiOies, which can eafily infure 

 their fafety among the rocks, by agility in fwim- 

 ming, or by the facility of finding a retreat in 

 their cavernous receptacles, or of there defend- 

 ing themfelves againft their enemies, by the ar- 

 mour which Nature has beflowed, liave all of 

 them lively and Ihining colours, the cartilaginous 

 excepted : fuch are the blood-coloured crabs, the 

 azure and purple lobfters, called langoiifte and ho- 

 mard, and, among others, that to which Rondelet 

 has given the name of Thetis, on account of it's 

 beauty, the violet-coloured urchins, armed with 

 points and fpears, the nerits, inclofed in a fpiral 

 cafe, with rofe and gray-coloured ribbons winding 

 round it, and an endlefs variety of others. 



It is very remarkable that all fliell-fi(h which 

 walk and migrate, and, confequently, have the 

 power of chooling their afylum, are thofe, in their 

 kind, which have the richeft colours : fuch are the 

 nerits which I have juft mentioned, the purple- 

 fifli, or Venus Ihell, refembling poliflied marble, 



the 



