508 PHILOSOPHICAL TRANSACTIONS. [aNNO 1731. 



ripe, anil never envelopes the organs of generation when young; so that the 

 Doctor thinks it can by no means be called a petalum, nor even properly a calyx: 

 and therefore he has given it the name of placenta, whose office it certainly 

 performs. 



The Doctor has not been able to observe exactly the structure of the organs 

 of generation, because of their excessive smallness; but they appear to the 

 naked eye as represented in the figures, and in Plum. N. G. tab. 8. The Dor- 

 stenia sphondylii folio, dentariie radice of Plumier differs from both of the 

 Doctor's; for, in the former's drawings, done by order of the late king of 

 France, of which the Doctor had seen a copy in the collection of the late Dr. 

 Sherard, the leaves are represented serrated, the placenta quadrangular, and 

 the roots consisting of several knobs tied together lengthwise. From which 

 last particular, the Doctor is persuaded that the root of that species is the dra- 

 kena radix, mentioned by Clusius in his Exotics, p. 83. 



Concerning Diamonds found in Brazil. By Dr. De Castro Sarinento. 

 N°421, p. 199. 



Dr. De Castro had the following account of diamonds from a gentleman, 

 who for these 15 years last past had lived and dug gold in the mines of Brazil, 

 and who brought from thence several diamonds of considerable value. 



Near the Prince's town, capital of the county Do Serro do Frio, belonging 

 to the government of the gold mines, there is a place called by the natives Cay 

 the Merin, where they used to dig gold for many years, as also from a small 

 river, called Do Milho Verde. The miners, that dug gold in those places, 

 turned up the grounds and sands of the banks of the said river, in order to 

 extract the gold from them, and by so doing found several diamonds, which then 

 they did not prize as such ; for, some of the miners kept several stones for their 

 figure and curiosity, which, though so valuable, by length of time they neg- 

 lected and lost, and did so till the year 1728, when one of the miners coming 

 to work there, and being better acquainted, deemed them to be diamonds, and 

 made experiments on them; and finding them really such, began to seek for 

 them in the same ground and sand, where the former miners had ignorantly 

 left them; and the rest of the people followed his example. 



Having thoroughly examined those places, they began to search for them in 

 the river itself, and they actually found diamonds there, but with more diiii- 

 culty and trouble. In the former places they found them together among the 

 earth and sand, as they lay ; but in the river, as the sand is more dispersed, 

 they lie farther asunder. 



