HoLLOWAY. — Studies in the New Zealaiid Species of Lycopodium. 301 



L. laterale, and L. Drummondn ; and a parallel type in L. voluhile, 

 L. densum, L. fastigiatum, and L. scariosum. From the comparative 

 study of the main stems, the roots, and the branches of all of these 

 species, and of the development of the vascular strand in the young 

 " seedling " plants of eight of them, it has been concluded that the 

 radial or stellate type is probably to be regarded as most closely repre- 

 senting the primitive one for the genus, and that the mixed and the 

 parallel types are modified forms of it. 



In the main, the particular subdivision of the genus into sections 

 adopted by Pritzel is in accordance with the facts known concerning 

 both the sexmil and the asexual generations of the various species. The 

 Selago and Phlegmari<i sections comprise species which are orthotropic 

 when growing terrestrially, and pendulous when epiphytic. The pro- 

 thalli of six of the species — viz., L. Selago, L. Hippurls, L. Phlegmaria, 

 L. Billardieri, L. nummularifolium, and L. carinatum — are known : 

 they belong to one or other of the two types, Selago and Phlegmaria, 

 which both Bower and Lang would consider to be more or less closely 

 related. The form of the embryo plant is simple, being uncomplicated 

 by the presence of a large foot or a protocorm. The vascular cylinder in 

 eieven species has been investigated by„ Jones (1-3), and also in L. Selago, 

 L. Billardieri, and L. varium in the i^resent paper, and has been seen 

 to be constantly of the radial-stellate type. In the Inundata and 

 Cernua sections occur those species whose prothalli aie of the L. cernuum 

 type, and Avhose young plants pass through the protocorm stage. This 

 is known in five species — viz., L. inundatuin, L. cern^ium, L. laterale, 

 h. ramtdosum, ancl L. salakense. The structure of the vascular cylinder 

 is mixed with extended protoxylem groups, this being especially charac- 

 teristic of L. c<ernuum and L. salal-ense,- and also of L. latierale and 

 L. Drumino7idii; and Jones has noted the broad protoxylem groups in L. 

 inundatum. Two species, L. voluhile and L. densum, included by Pritzel 

 in the Cernua section possess characters which possibly would justify 

 their removal from this section. They both" show the parallel structure 

 Oi the vascular tissues, and both possess a large subterranean prothallus. 

 The species in the Clavota section would seem to be closely connected with 

 regard to their main characters. The prothallus has been found in five 

 species — viz., L. annotinum, L. clavatum, L. fastigiatum, L. complana- 

 tum, and L. scariosum — and belongs to one or other of the two large 

 subterranean types, 7v. clavatum and L. complanatum. The large foot 

 is characteristic of the embryo plant of these species. The vascular 

 cylinder has been investigated by Jones in five sj^ecies and by the 

 23resent writer in L. fastigiatujn and L. scariosum, and shows constantly 

 the parallel structure. 



The question arises, are these main sections of the genus which 

 correspond so closely with the chief characters of both the gametophyte 

 and the sporophyte generation to be regarded as more or less nearly 

 related to one another, or as widely separated? The latter is the con- 

 clusion arrived at by Bruchmann (6, pp. 108-9) fi'om his study of the 

 prothalli of four European species. Lang (14, pp. 305-6), on the other 

 hand, believes that the different prothallial types are " all more or less 

 profound modifications of a type not unlike that of L. cernuum. The two 

 forms of prothallus found in L. Selago give the clue " to the specializa- 

 tion of the subterranean saprophytic types on the one hand and of the 

 epiphytic tvpe on the other. With this view Bower (4) is in close agree- 



