492 



" Cams " plenty of Silavis piatensis springs into flower when the 

 CEnanthe has vanished. My observation of the plant at Fareham 

 enables me to corroborate Dr. Bromfield's account (Phytol. ii. 241) of 

 the uncertainty of its appearance. In 1843 it was abundant in the 

 Salterns, and in 1844 not a plant was to be found there, while in 1844 

 it was plentiful in the field at Cams, where J had not previously seen 

 it. A similar instance is mentioned in an interesting work, ' Wild 

 Flowers of the Year," in the disappearance of Spiranthes autumnalis 

 from a field at Tunbridge Wells in 1844, where, in the previous year 

 it was extremely abundant. It seems desirable that those plants 

 should be noticed which are subject to these periodical disappearances, 

 and, as far as can be, the causes traced. I have in a former paper 

 mentioned Thlaspi arvense to possess such a character. 



The oxlip [Primula vulgaris, (3. caulescens) grows, though very 

 sparingly, in a copse at White-dell ; and here I found it in a curious 

 state, of which I had previously heard, but never before had an oppor- 

 tunity of observing, viz., true primroses and oxlips (i3. caulescens) 

 growing from the same root. There were several specimens which 

 exhibited the same phenomenon. 



Carex extensa, which grows in great plenty at Cams, just a little 

 further from the edge of the water than Statice rariflora, puts on a 

 caespitose appearance, which I have not seen noticed. It grows in 

 tufts or stools of considerable size. In the Salterns, where there are 

 a few plants of it, it does not assume this character. At Cams it has 

 to push its way through shingle, and it grows in a clayey soil full of 

 pebbles : this may perhaps have some influence on its mode of 

 growth. 



In gathering a quantity of specimens of Pyrus communis to be 

 dried as duplicates, from the only wild specimen in the district, I no- 

 ticed a curious circumstance after bringing them home, a distance of 

 about two miles ; on turning them out for the purpose of putting 

 them in press, I observed that they possessed a very offensive odour, 

 exactly like that of Chenopodium olidum, only not in so powerful a 

 degree, and having no other plants with me at the time, it could not 

 have originated with another plant. 



Potamogeton plantagineus is very abundant on Titchfield Common, 

 and 1 think it will eventually be found to be no uncommon plant in 

 boggy situations. I remember seeing it at the new reservoir, Daven- 

 try, Northamptonshire, in great plenty, though at the time I was un- 

 acquainted with it. 



The radiate variety of Centaurea nigra is very abundant : is this 



