10.2 CARL SKOTTSBERG, A BOTANICAL SURVEY OF THE FALKLAND ISLANDS. 



In his book on Kerguelen plants {39), p. 323, Dr. E. Werth has opposed my 

 biological interpretation of the Accena-ilower, published in Feuerl, Bluten. He comes to the 

 conclnsion that the species of tliat genus are entomogamous and not anemogamous, 

 as vvas once the opinion. The filaments of Accena adscendens are short and stiff, 

 the pollen-grains coherent and not so easily carried away by the wind. No visitors 

 were observed by him, but he supposes that, in South America, the species is visited 

 by insects, and finds, that af ter what he has observed on the Kerguelen Accena, 

 there is no doubt as to insects as agents, if the flowers are cross-fertihzed. The 

 Kerguelen-plant is most decidedly autogamous. My description of the Fuegian spe- 

 cies gives the impression, he says, of having been drawn from dried material. This 

 is, however, not the case. The observations were made on living plants, and the 

 closer description as well as the figures are based upon material preserved in alcohol. 

 It is now evident, that there is a certain difference between the Accena adscendens 

 of Kerguelen and of Tierra del Fuego, for in the latter, the filaments are considerably 

 longer than in the plants described and figured by Werth, and they are easily 

 moved even by a light breeze. That the colour of the flowers, the shape and size 

 of the stigma etc. are of an anemogamons type, cannot be denied, but I quite agree 

 witli Dr. Werth, that these facts do not prove anything, for there are beautiful 

 exceptions, such as Sanguisorba officinalis L., just quoted by him. However, 

 the flowers of this plant produce honey. But this is not the case with Accena. The 

 insects would then be attracted by the pollen. However, I cannot see but that the 

 small quantities of pollen, presented at the top of long, w^eak filaments as in the 

 Fuegian plant, do not remind one much of the constructions generally characteristic 

 of pollen-flowers. There is also another fact that does not fit in w^ell with Werth's 

 explanation: the frequent occurrence of female individuals, described by me and 

 låter also by Werth. They have nothing whatever to offer their supposed visitors 

 and I should think, that insects leave them alone. If the wind does not effect 

 the transport of pollen, the occurrence of pure female plants — and they are 

 not at all rare — seems to me impossible to understand. Thus, I feel forced still 

 to regard the Accenas in general as fertilized by the wind, even if they do not possess 

 such a pronounced anemogamous construction as Poterium, but rather seem to hold 

 an intermediate position between this genus and Sanguisorba. 



5. Tlie plant associations. 



All the predominating associations found in the Falklands are closely related to 

 eacli other. The climatic conditions are nearly the same all över the Islands — if 

 differences occur, they reveal themselves in the distribution of certain species (see 

 p. 86), all of them being comparatively rare; the character of the vegetation seems 

 to be the same everywhere. Also the edaphic conditions are indeed monotonous, 

 for peat of some kind generally forms the soil. The vegetation varies in accor- 

 dance with the mechanical composition of the subsoil, some kinds being dryer, others 



