136 The Flora of Wiltshire. 
iii. ¢. 2. R. aquaticus albus, circinatus tenuissime divisis foliis, 
floribus ex alis longis pediculis innixis. Raii Syn. ed. 3. 249.” 
Locality. In canals and marsh ditches, also in ponds, which 
preserve an uniform level. P. Fl. May, June. Area. * 2. * 4. 5. 
South Division. 
2. South Middle District. In the Kennet and Avon Canal near 
Devizes. 
North Division. 
4. North-west District. In the canal near Bradford and Chip- 
penham. 
5. North-east District. In the canal leading from Swindon to 
Cricklade, also at Purton. 
The above localities are the only ones I quote for this plant 
as noted in my Botanical rambles. It will be probably met 
with in all the districts, but the pantothrix form having been fre- 
quently mistaken for it by many of my correspondents, there 
appears much uncertainty respecting many of the localities sent 
me, and I therefore hesitate to quote them for the present. This 
plant which was first distinguished as a species by Professor Sib- 
thorp in his Mora Oxon, may be known from the true R. aquatilis, 
as Mr. Babington well remarks, by its small sessile flat leaves, 
which are all divided into finely capillary rigid segments, disposed 
in one orbicular plane. In R. aquatilis the leaves are stalked, the 
submersed ones very much divided into threadlike segments, 
spreading in all directions, so as to form a spherical mass, whilst 
in R. fluitans (which has not as yet been noticed in’ Wiltshire), 
R. fluviatilis of Sibthorp, the leaves are stalked, but the submersed 
ones are divided into a few very long repeatedly forked segments, 
which lie parallel with each other in the water. The leaves of this 
latter plant are often many inches in length, and retain the same 
structure even when growing in stagnant ponds and ditches. I 
have observed the leaves of “ R. circinatus coated with earthy par- 
ticles, in the same way as those of Chara, though less extensively. 
3. R. cenosus (Guss.) Mud Crowfoot. Eny/. Bot. Suppl. t. 2980. 
Only observed as yet in small quantity on mud, by the road-side 
near Marston Meisy. I should be greatly obliged for any additional 
