Laing.— 0;i Lessonia variegata. 307 



yellow in colour, closely covered with linear markings from 

 ■Jin. to ^in. in length of a darker colour. Hence the specific 

 name.* 



Fructification. — The sori are of the usual type, and of 

 irregular size and shape, generally several inches in length, 

 and situated in varying positions on the fronds, more often, 

 perhaps, immediately above the middle than elsewhere. I 

 have, however, found them within an inch of the base. Ac- 

 cording to Harvey, in the "Flora Antarctica," the sori in 

 L. fuscescens are situated bej^ond the middle of the leaf; and 

 Agardh (" Species, Genera, et Ordines Algarum," vol. i., p. 150) 

 makes their situation at the middle of the frond a generic 

 character. Harvey also states that the cuticle covers the 

 sori. Tliis is certainly not the case in L. variegata, in which 

 the sori are on the surface of the frond ; and, as Agardh 

 points out in the case of the other species, it is probably also 

 a mistake due to the coherence of the parts in dried speci- 

 mens. 



Groivth. — In the youngest specimens seen the plant con- 

 sists of a single stem surmounted by a leaf, and at this stage 

 is scarcely distinguishable from young plants of Macrocystis. 

 In the latter, however, the first fission of the frond is scarcely 

 median, and this character at present serves to distinguish it 

 from Lessonia, in which the division passes through the centre 

 of the lamina, and in which all leaves subsequently formed 

 apparently result schizogenetically from the first leaf, so that 

 if the growth were regular the plant ought to consist of a 

 single stem presenting a perfectly dichotomous symmetry in 

 one plane ; but, owing to the twisting of the stem already re- 

 ferred to, the branches are thrown out of the original plane ; 

 and, owing to the thickening and coalescence of their lower 

 portions, there appears to be a number of stems in place of 

 one arising from the root. This, at any rate, seems to me the 

 most feasible explanation of the large number of stems ap- 

 parently growing from the rhizoid in the mature plant. As 

 there is no proliferous growth or adventitious branching, it 

 cannot be accounted for by these means ; and the only other 

 possible explanation that occurs to me is that the mature 

 plant represents a cluster of plants growing together. Against 

 this idea is the fact that young plants are not seen growing 

 from the rhizoid, and that all the stems are apparently of 

 similar age. In favour of the explanation first given is the 

 great lateral thickening by secondary growth that is clearly 

 shown at the base of the stems, and the fact that sometimes 

 two masses of central tissue are found in one stem, and this 



* If the fronds are steeped in fresh water for an hour or two they 

 blister badly, probably owing to osmosis. 



