HoLLOWAY.— .S7wc?*es in the New Zealand Species of Lycopodium. 225 



seen only in certain standard books of reference, show that a tubercle is 

 at once initiated, which is apparently at first devoid of fungus. This 

 tubercle was called by Treub the " primary tubercle," and he supposed 

 that it was a characteristic feature of the Lycopodium prothallus. He was 

 also successful in experimentally cultivating the prothalli of L. salakense. 

 This also begins with a globular body, the " primary tubercle," from which 

 several thin filamentous branches arise, one of the latter eventually thicken- 

 ing and producing the sexual organs. This prothallus remains altogether 

 free from a symbiotic fungus. Treub also germinated the spores of L. curva- 

 tum Sw., from which he obtained " primary tubercles," but he was unable 

 to induce them to develop farther. All the mature prothalli of L. cernuum 

 which I have found show the rounded basal tubercle, although in some 

 instances this is somewhat pointed below (see 7, figs. 17-21, and figs. 38-44: 

 in the present paper). 



I have dissected out a number of young prothalli of the species L. ramu- 

 losum along with the more mature forms, and some of these are shown 

 in figs. 61-65. I judge these to belong to this species since they are of the 

 typical Lycopodium form and no other species of Lycopodium were present 

 in the two localities from which they came. No other kind of prothallus 

 was ever found by me in the turves from which I dissected out those of 

 L. ramulosum, nor was any species of fern present in the near neighbourhood, 

 except Gleichenia dicarpa. Finally, the individuals which are shown in 

 figs. 61-65 form a series which leads on to the more mature prothalli 

 which undoubtedly belong to L. ramulosum. The youngest prothallus was 

 that shown in fig. 61. In it there was no basal swelling, nor was there any 

 indication of the presence of a fungus. The lower half consisted of a single 

 linear row of cells, whilst in the .upper half there was a gradual increase 

 in the number of cells and in the girth of the filament towards the apex. 

 This upper half was not a flat expansion of cells as in the usual fern pro- 

 thallus, but was radial in build. The cells at the apex were smaller than 

 those farther back, and evidently functioned as the meristem. The whole 

 filament contained chlorophyll corpuscles. The original spore-case w:as 

 still attached to the basal cell. In fig. 62 is shown a j^rothallus in which the 

 fijst-formed filamentous stage was very short, passing almost immediately 

 and suddenly into a globular mass of cells which could be called the 

 " primary tubercle." This prothallus also was quite free of fungus, being 

 green througTiout. The apical region consisted of small-celled tissue, and 

 a young sexual organ was developing near by. A group of rhizoids was 

 borne on the basal tubercle. In the formation of a fungusless primary 

 tubercle this young prothallus corresponds very closely to those early 

 stages in L. cernuum, L. salakense, and L. curvatum described by Treub. 

 With regard to the mature prothallus of L. ramulosum, the conclusion I 

 arrived at was that any swelling In the fungal regions was primarily due to 

 the localized presence of the fungus. From these other three species, how- 

 ever, it is apparent that there may be at first a primary tubercle quite 

 apart from the presence of the fungus, and this also appears in such a young 

 prothallus of L. ramulosum as that shown in fig. 62. However, this is not 

 always the case, as in the particular prothallus shown in fig. 61. The three 

 young prothalli shown in figs. 63-65 all possessed a primary tubercle, which 

 was infested by fungus. 



Are we to consider that a primary tubercle is a fundamental feature 

 in the structure plan of the Lycopodium prothallus, or is it to be regarded 

 as an added feature ? Possibly we are to regard the radially-built filament 

 8— Trans. 



