﻿B&7 



infer from this and from Hill's reference to "a pension" that 

 Young's active services had been dispensed with, but that he still 

 retained his title : but we know no more of him. In the ten years of 

 his life of which we have any record he had risen from " nurseryman 

 nor" to the dignity of a bag- wig, sword, and gold lace. 

 His most enduring memory will be found in the two volum 

 are now for the first time fully described. 



James Britten. 



POTAMOGETON RIVULARIS Gillot. 

 By Alfred Fryer. 

 Recently Mr. Bennett sent me specimens of a Potamogeton 

 which he had received from Dr. Magnin, labelled " P. rivularis 

 Gillot, Montemerle, Saone et Loire, France, 1883, leg. Dr. Gillot," 

 with a request for my opinion thereon. At the first glance I was 

 struck by the resemblance these specimens bore to P. lanceolatm, 

 and after a long comparison with many species and hybrid forms 

 of PntuHuujrton, I wrote to say that the plant was probably a form 

 of lanceolatm, but my own herbarium did not afford sufficient means 

 for a thorough comparison. My friend, by way of reply, kindly sent 

 me the matchless set from his own herbarium, together with the 

 many notes and letters from eminent botanists on the Burwell Fen 

 form of the true P. lanceolatm Smith. 



With these valuable aids I was not only able to regard the P. 

 rimhn-h as a variety or state of P. lanceolatm, but I acquired what 

 seemed to me strong evidence in favour of a view I have long held, 

 that 'anredatus itself is a hybrid rather than a true species. To 

 these opinions Mr. Bennett replied, " I entirely agree with you as 

 to P. rivularis being so near lanceolatm (of course we understand 

 they may not be absolutely identical), that it seems impossible to 

 separate them in the aggregate." To the question of hyhrflit,, my 

 friend made no reply, but shortly afterwards wished me to send a 

 note on P. rimlariito the Journal of Botany. I think I do not err 

 in interpreting the request of my friend that I should undertake a 

 task so obviously his. to a desire on his part that the whole subject 

 should be fully ventilated, and that the possibly erroneous views 

 I entertain should neither be ignored nor supported by him. I trust 

 this explanation will be sufficient to acquit me of the charge of 

 presumption in writing about a subject which Mr. Bennett has 

 made essentially his own. 



For the purpose of enabling students to understand the views 

 I wish to express in this note, it will be necessary to give, in the 

 first place, a short description of each of the two forms :— 

 Potamogeton rivularis Gillot. Potamogeton lanceolatus Smith. 

 Stem filiform, somewhat com- Stem very slender, compressed 

 pressed, dichotomously branched, or flattened, with secondary 

 internodes shorter than the sub- branchlets, internodes sometimes 

 tending leaves. longerthanthesiibtendin-l iu h. 



Journal of Botany.— Vol. 32. [Nov. 1894.] z 



