254 Mr. W. H. Lang. Preliminary Statement on the 



Scolopendrium vulgare, I/., var. ramulosissimum, Woll. The cultures 

 of this fern were made in the manner already described for Lastrcea 

 dilatata. The spores were obtained from a plant grown in the open 

 air in the Royal Gardens, Kew. 



The prothalli were at first heart-shaped, and on many of them 

 normally produced embryos developed. No further changes ensued 

 in those on which young plants were present, and they soon became 

 colourless and died. In those which had remained unfertilised, how- 

 ever, the apex continued directly into a cylindrical process,* which 

 was of considerable thickness, and in some cases attained a length of 

 5 mm. The lateral portions of the prothallus showed no further 

 growth, and became in time brown or colourless appendages to the 

 base of the cylindrical process. On the process were numerous 

 archegonia, and its prothallial nature was still further shown by the 

 presence, in. some instances, of thin lobes of tissue, which generally 

 bore antheridia. Sections through the process in this stage show 

 that the archegonia are normally formed, and reach almost to the 

 apex, and that tracheides are absent from the tissue. The archegonia 

 are capable of fertilisation, for in some instances normally produced 

 embryos were found. 



After the process has in this manner attained a greater or less 

 length, its tip becomes yellowish, contrasting with the deep green 

 colour of the region behind. Near the apex ramenta develope, which 

 soon completely clothe the tip of the process and render it white and 

 conspicuous. Archegonia are present to just below the ramenta. 

 Longitudinal sections at this stage show that one or two small eleva- 

 tions corresponding to the rudiments of the apex of the stem, and the 

 first leaf of the sporophyte have been formed. Beneath the broad tip 

 a flat mass of small meristematic cells extends ; the meristematic 

 tissue is continuous with that of the stem and leaf apices, but, on 

 passing away from these, is separated by several layers of large, non- 

 meristematic cells from the surface. In a slightly older stage the 

 stem apex has become conical, and a number of leaves have formed 

 which are circinately curved, and form a bud clothed with ramenta. 

 In the meristematic mass numerous tracheides have been developed. 

 One large group is central in position, and extends to the limit 

 between prothallial and sporophytic tissue, while others are found 

 beneath the bases of the leaves, and are in continuity with their pro- 

 cambial strands. The apex of the stem is occupied by an initial cell, 

 the relation of which to the initial cell or cells of the apex of the 

 process has not yet been traced. The young sporophyte appears to 

 be a direct continuation of the process. It is possible that some of 



* Prothalli of Scolopendrium, which from the brief description given of them 

 appear to have borne similar processes, are mentioned by E. J. Lowe, in the ' Gard. 

 Chron.,' November 10, 1895. They were not investigated further. 



