^8 Natural Hiftory 



The calcarioiis Coat commences thin where the Trunk 

 begins, grows thicker as the Branches advance ; and the 

 youngefL Fibres have, generally, by much the largeft Propor- 

 tion, if not the largeft Qaantity furrounding them: This 

 Part iikewife, when throv/n into the Fire, yields fomething 

 of a marine horny Smell. If we examine this Coat attentive- 

 ly, even with the naked Eye, we may difcover in many 

 kinds, regular Orders of Pores or Cells ; and, viewed by the- 

 Mrcrofcope, it conftantly appears to be an organical Body, 

 and not the accidental Concretion of adventitious Siibftances, 

 like the indurated Cruft upon Mofs and other Vegetables in 

 petrifying Waters, but a regular Congeries, like the Cells in 

 which Animals have been formed, or exifted. 



Moftofthefe kinds of Bodies, whan per feEi^ exhibit the 

 Appearances defcribed \ but we often fee thefe horny Shrubs 

 in the CoUedions of Naturalifts, without any calcarious Co- 

 vering at all. It muft not however be immediately de- 

 termined, that they were fo formed ; fince it is more than, 

 probable, that they have been divefted of thefe Coverings,, 

 by the Violence of the Waves, and other hke Accidents ; by 

 which they have been ftripped of a Part, that feems not 

 lefs eflential to thefe Bodies, than the Bark is to Trees. This 

 accidental Change in their external Habit, has, neverthelefs,, 

 occafioned fome Difficulty to the Botanifb ; and induced 

 even Boerhaave himfelf,. to divide them into two Families, 

 calling thofe that had their native calcarious Covering T^itano- 

 Keratophyta ; and thofe that were divefted of it, which on; 

 the Sea-coaft will foon happen, only Keratophyta. 



Notwithflanding thefe ftrong Circumftances, to prove the 

 animal Strudure of thofe fubmarine Bodies, yet as there are 

 many curious and ingenious Perfons, who ftill remain uncon- 

 vinced, it becomes necefiary for us to fcrutinize into the Na- 

 ture of them with more Exadnefs. 



Specimens 



