The Scottish Naturalist. 



191 



POA PALUSTRIS L- IN PERTHSHIRE- 

 By F. Buchanan White, M.D., F.L.S. 



ON the sides of the river Tay, below Perth, are more or less 

 extensive marshes which, being flooded at every tide and 

 rich in fluvial mud, sustain a rankly luxuriant vegetation. From 

 the softness of the ground, which renders many parts almost 

 inaccessible, these marshes have until lately not been so carefully 

 examined as they deserve. This year, however, my friend Mr. 

 William Barclay has been making as complete a catalogue as 

 possible of all the plants he found in a stretch of about six miles 

 on one side of the river. In the course of his investigations he 

 recently found a grass which, whilst bearing some resemblance to 

 Poa prattnsis, seemed to be distinct from that species. Further 

 examination convinced us that it must be Poa palustris. I sent 

 a specimen to my friend Mr. A. Bennett who forwarded it to Dr. 

 Hackel and he has confirmed our determination. 



Some weeks after the discovery of this grass in the Tay marshes 

 we happened to be exploring a marsh near Crieff, and here again 

 we found Poa palustris. Since this second locality is about 16 

 miles distant from the first and has no connection with it, it seems 

 not improbable that P. palustris may also occur in other places. 



From P. nemoralis, which, of our common grasses, is most like 

 P. palustris, the presence of a conspicuous ligule in the latter is a 

 good mark of distinction. The ligule and the absence of stolons 

 separate it from P. ptatensis, and the obsoletely nerved lower 

 pale from P. trivialis. 



A NITELLA NEW TO THE BRITISH FLORA. 

 By Ar. Bennett, F.L.S. 



LAST Autumn Mr. King sent me a specimen of a Nitella 

 gathered by Mr. W. S. Duncan in the Outer Hebrides. 

 This, though seemingly referable to Aitella batrachosperma, A. 

 Braun, was held by Messrs. Groves to be too immature to speak 

 positively about. This summer my friend Dr. Ward wrote me 

 that Mr. King had sent him fresh specimens of a Nitella from the 



