POLYGONUM 425 



This rather pretty form, which appears to be a distinct sub-species, 

 is found in dry sandy soil, as at 



1. Isis. Longworth. Faringdon. 2. Ock. Boar's Hill. Cothill 

 Frilford. Besilsleigh. Didcot. 3. Pang. Bradfield. Tile 

 hurst. 4. Kennet. Mortimer. Ufton. Hampstead Marshall 

 5. Loddon. Sonning, Budge. Shinfield, Tufnail. Hurley 

 Ambarrow. Sandhurst. Bracknell. Binfield. Bray. Eathei 

 frequent in this district. 

 The var. angusti/oHum, S. F. Gray, 1. c, is earlier than the name 

 given above ; it is based on Polygonum oblongo angustoque folio, Ray, Syn. 

 146, n. 3. 



A form which occurred on the saline meadow at Marcham had 

 more fleshy leaves, and was thought by Mr. J. G. Baker, who was with 

 me when it was gathered, to be var. Httorale (Link). Mr. A. Bennett 

 thought it was agrestinum, and the Eev. E. F. Linton considered it to 

 be a form of var. rurivagnm. Specimens were distributed through the 

 Bot. Exch. Club in 1892. 



Many plants do not satisfactorily come under any of the preceding 

 varieties. 



P. aviculare occurs plentifully in all the bordering counties. 



P. Hydropiper, Linn. Sp. PI. 361 (1753). Water Pepper. 



Hydropiper, Gerard, 361. 



Top. Bot. 355. Syme, E.B. viii. 70, t. 1234. Nyman, 638. Fl. Oxf. 257, 

 Native. Paludal. Wet places, ditches, stream-sides, damp hollows, 

 and ruts in woods. Rather common, especially in heathy dis- 

 tricts, and, as in Windsor Park, marking the damper places of the 

 rides by its profuse growth. A. June-October. 

 First record. Sunninghill, Sir Jos. Banks, 1773. Sonning, Mr. S. 

 Budge, in Herb. Brit. Mus. 1800. Published as P. hydropiper, Mavor's 

 Ayr. Berks, 1809. 



1. Isis. Wytham. Appleton, &c. Local and somewhat rare in this 



district. 



2. Ock. Marcham, Walker. Bagley Wood. Ferry Hinksey. South 



Hinksey. Kennington. Tubney. 



3. Pang. Oare. Cold Ash Common. Ashampstead. Tilehurst. 



Bucklebury. Fence Wood. 



Too frequent in the damp woods of the Kennet and Loddon dis- 

 tricts to require an enumeration of localities. 



P. Hydropiper x Persicaria. This hybrid bears considerable re- 

 semblance to P. mite, fi-om which it differs by its larger fruit, thicker 

 spikelets, and more divaricate habit. Both of the assumed parents 

 were in the vicinity. The nuts appear to be mostly infertile. 



Near Hinksey and Hurst Green. 



P. Hydropiper occurs in all the bordering counties. 



