Biographical Memoir ofBarofn de Beauvois. SI 



also capable of rising to more general considerations ; and that 

 none of the more difficult questions of botany were unknown to 

 him. 



But his printed writings are not the only ones which he intend- 

 ed for the public. We have seen among his papers very exten- 

 sive treatises on various branches of the history of animals and 

 plants. He had nearly completed the relation of his travels in 

 Africa, and had begun those in the United States. He had en- 

 gaged in the study of vegetable physiology, and several times 

 comnumicated observations in that department to the Academy, 

 of which we have taken notice in the annual reports. What 

 remained to him of his collections, after all his losses, were still 

 of importance. In a word, there was nothing wanting to him 

 to enable him to occupy himself usefully both for himself and 

 the public during a long life, had nature granted him one ; and 

 nothing seemed to render the contrary probable. His health 

 was good, his life regular, his habits simple and moderate, and 

 he employed temperance even in his studies. All these ap- 

 pearances were deceitful. The sudden change of temperature 

 which happened at the commencement of the present year, occa- 

 sioned an inflammation of the chest, which, in defiance of all the 

 efforts of art, carried him off* in five days. He died on the 21st 

 January 1820, leaving no children, although he had been twice 

 married. 



On the general presence of Spiral VesseU in the Vegetable 

 Structure ; and on the peculiar Motion observable in de- 

 tached pieces of the living Bark <yf Urtica nivea. By Mr 

 David Don, Libr. L. S. &c. Communicated by the Au- 

 thor. 



J-T has been generally believed that spiral vessels are rarely 

 found in the parts of fructification ; but repeated observations 

 have convinced me that they are to be met with in almost every 

 part of the vegetable structure. I have found them in the ca- 

 lyx, corolla, filaments, and style of Scabiosa atro-purpurea and 

 Phlox ; in, the calyx and petals of Geranium sanguineum ; in 

 the perianthium of Sisyrinchium striatum ; in the capsule and 

 styles of Nigella hispanica. They are also present in the peri- 

 carpium of Onagrarice^ CompositcCy and Malvacece. I have 



