96 
The Irish Naturalist. 
April. 
2. Forms. — The forms are numerous and puzzling. 
Mr. Baker and I (loc. cit.) described as varieties, vulgare, 
F. Schultz ; ochreatum, DC. ; pseudo-repens, H. C. Watson ; 
longipedunculatum, F. Schultz ; repens, Koch. But now 
certain conclusions have at length ripened in my mind, 
which are rather at variance with that arrangement. The 
first is that these varieties " represent only a few out of 
numerous forms, all equally capable of description, which 
the plant assumes. The varieties named happen to have 
been pitched on by collectors in past years, and described ; 
and so they have got into our hand-books. They repre- 
sent, in fact, certain stages, or steps, or extremes, of varia- 
tion in a few directions, but leave the student uninformed 
of the large variety of directions and degrees in which the 
species varies. The number of characters in which varia- 
tion occurs is of course great ; e.g., size of plant, vigour, 
compactness, production of roots or rootlets at the nodes, 
direction of stems or branches {i.e., prostrate, ascending, &c.), 
shape and number of leaflets, length of peduncle, presence 
and number of involucre-bracts, number of rays in umbel, 
and so on. The degree of variation in each of these 
characters, again, differs considerably. Now, it is a fact 
that a large number of the possible combinations of these 
variations of character may be found in a long series of 
specimens " ; and to describe and name every distinct 
form would be a very large undertaking. 
A second conclusion is this : that there are often found 
" upon one plant, springing from one root, more than one 
of these distinct forms." To take the rooting-character 
as an example. " nodiflorum normally consists of a 
root, from which a more or less upright flowering stem 
proceeds ; and there are numerous nearly prostrate side 
stems or branches from the root, each of which may both 
flower and root.'' " The rooting character may be present 
in all the side stems, of course at the nodes only ; even 
if for any reason the stems or branches are not actually 
prostrate, if e.g., they are carried up a hedge, or held up 
among herbage, they often show little embryo roots or 
processes which in contact with the ground might develop 
