312 PHILOSOPHICAL TRANSACTIONS. fANNO l676v 



newly brought from shore, nor could I easily perceive it had any relics of its 

 late corruption. 



That the testicles of the animal called musk-quash do smell strong of musk, 

 as Mr. Josselin says, in N° 85, is most certain : for, I have known some of 

 them kept a long time in a pocket, till they were become hard and black, and 

 yet smelt as strongly as at first ; which, in my opinion, was nothing inferior to 

 the scent of that which is commonly sold for musk in the shops. 



On the Texture of Trees', and on Animals in IVlne, In a Letter from Mr. 

 Leewenhoeck, Delft, April 21, 1676. N° 127, p. 653. 



M. Huygens was pleased to show me the comparative anatomy of the trunks 

 of plants, written by Dr. Grew; and told me that he had very ingeniously and 

 learnedly discoursed on that subject; though I, by reason of my unskilfulness 

 in the English tongue, could have little more than the pleasure of viewing the 

 elegant cuts. 



I have formerly written to you, that I had discovered in several trees two 

 sorts of vessels^ or pores, and conceived, that the matter which serves for the 

 increase of trees was in the greater vessels sent upwards,^ and that some small 

 particles again descended in the smaller vessels, to the roots, whereby was 

 maintained a circulation^ also in trees. 



But not finding by the figures of Dr. Grew, that he has discovered those two 

 sorts of vessels in the woody part,* I here take the liberty of sending you the 

 eighth part of the transverse slice of an ash-sprig of a year's growth ; and now 

 acquaint you, that besides those two sorts of vessels in wood, I have discovered 

 a third sort ; these two going directly upward, and this third issuing out of the 



* These two sorts of vessels are described by Dr. Grew in his first and general Anatomy of Plants, 

 in his Anatomy of Roots, and in his Anatomy of Tninks. — "^ The chief use to which Dr. Grew, in 

 his said three books, assigns these vessels in all parts, is not the conveyance of sap but of air. And 

 herein Signor Malpighi agrees with himj see his Anatome Plantarum de part. Caulem componentibus. 

 Yet in some few plants, and at some certain times of the year only. Dr. Grew shows, that the said 

 air-vessels do contain an aqueous sap, and how it comes to pass ; see his Anatomy of Trunks, p. 2, 

 ch. 1, and pag. 26. — ^^ Dr, Grew, in his aforesaid first book, speaks conjecturally of a circulation, not 

 in the trunk but in the root only j and that not by vessels of a diff'erent but the same species, viz. sap- 

 vessels, some of them running through the pith, by which chiefly tlie sap may ascend, and some 

 through the bark, by which part of tlie sap may descend j see ch. 2, of that book. — * These two sorts 

 of vessels are, as was said, distinctly and largely described by Dr. Grew, particularly in his Anatomy of 

 Trunks, p. 22 to 30. And tlie explications of all the figures plainly distinguish the air-vessels from tlie 

 sap-vessels. The pores or mouths of which sap-vessels are from their incomparable smallness repre- 

 sented only in fig. 18, where they are very much wider than ordinary j see also p. 25, of that book. 



