102 DH. COCKS ON THE GROWTH, ETC., 



reappearance of many species of marine plants ; I at length dis- 

 covered that in this respect a very remarkable difference exists 

 between these and land-plants. 



For instance : — dating from the period when I first became a 

 collector, I ascertained that many of the plants which I originally 

 found growing in certain localities did not invariably reappear 

 under the same circumstances ; that is to say, they either dis- 

 appeared altogether, or remained in abeyance during the lapse of 

 a series of seasons ; whilst, in contrast, I found the same plants 

 growing in quite a new and different locality. I observed also 

 that there were a few species which I never found growing but in 

 the very spots where they were originally discovered ; for instance, 

 the " GriffitJisia secundijlora,'^ which was first found by my friend 

 the Rev. Mr. Hore growing near Bovisand in 1846, where I have 

 since been in the habit of taking it myself for many succeeding 

 years, occurs, I believe, in no other place in Great Britain. 

 I would also remark that, although I have visited this locality 

 at all periods throughout the year, with the exception of three 

 of the winter months, I have never yet found a single speci- 

 men of this plant in fruit ; but I am nevertheless inclined to 

 believe that, if specimens could be taken in December, January, 

 and Eebruary, they would be found to be in a state of fructifica- 

 tion. The impediments are, however, very great. The place in 

 which it grows is difficult of approach, even at the most favourable 

 times, and then only in a boat. Whenever the wind blows from 

 the south-west, or when the sea is rough, it is entirely unapproach- 

 able; and besides, on reaching the spot, it is invariably found 

 growing submerged to the depth of three or four feet at the lowest 

 spring- tides. 



In the years 1844 and 1845, I was fortunate in collecting some 

 very large and beautiful plants of CallitJiamnion roseum — not 

 an uncommon species. Since that period I have not succeeded 

 in taking any so fine, and for the last three years I have not 

 been able to secure a single good specimen. It is, however, 

 rather remarkable that in the spring of last year (1858) a 

 curious variety of this plant, which I had never before seen, made 

 its appearance. It was found growing in singular abundance, 

 and in several different localities ; and although I examined many 

 hundreds of specimens, I did not succeed in finding a single one 

 in a state of fructification. In the year 1849 I found another 

 species belonging to the same genus, viz. a remarkably slender 

 variety of CallWhamnion pedicellatifm, growing in luxuriant abun- 



