80 Transactions. 



Art. VII. — Studies in the New Zealand Species of the Genus Lyco- 

 podium : Part II — Methods of Vegetative Reproduction. 



By the Bev. J. E. Holloway, D.Sc. 



[Rend before the Philosophical Society of Canterbury, 6th December, 1916 ; received by 

 Editors, 30th December, 1916; published separately, 6th July, 1917.] 



Plates VIII, IX. 



It is characteristic of the lower classes of plants that they show great 

 capacity for vegetative propagation. With regard to the mosses this is 

 a common phenomenon. k ' In the pleurocarpous forms, the main axes 

 gradually die away from behind, the lateral branches becoming isolated, 

 and constituting the main axes of new plants. In probably the majority 

 of the Musci almost any portion of the body, a piece or stem, or a leaf, 

 will, under proper conditions, grow out into protonemal filaments, which 

 give rise to adult shoots in the usual manner. In certain species belonging 

 to the Bryineae, multicellular gemmae are produced at the apex of the 

 stem [and are either] modified leaves [or] are smaller and consist of but 

 few cells [or] are borne on long stalks. On being placed under . 

 favourable conditions, the cells of the gemma grow out into protonema." 

 (Vines, Text-book of Botany, p. 337, 1898.) 



Reproduction by gemmae is characteristic also of the Hepaticae. 

 " Brood-buds " have been described and figured as occurring in the Psilotaceae 

 (e.g., Engler and Prantl, 1900). Also, in Ophioglossum vulgatum, two 

 observers, Land (1911) and Pfeiffer (1916), have recorded that vegetative 

 reproduction, probably by adventitious budding of older roots, is the 

 common method of spreading. 



In the genus Lycopodium we find a variety of methods of vegetative 

 reproduction which are closely analogous to those cited above. The present 

 paper is devoted to a description of the methods of vegetative propagation 

 which I have observed in the New Zealand species of the genus Lycopodium,. 



I have not been able to gain access to Treub's Etudes sur les Lyco- 

 podiacees, in vol. viii (1890, pp. 14-23) of which is his description of the 

 root-tubercles of Lycopodium cermtum. 



I. Vegetative Propagation of the Prothallus. 



Treub (1886) has described three methods of vegetative propagation 

 which he observed in the prothalli of L. Phlegmaria. Firstly, by the pro- 

 gressive rotting of the older parts of the prothallus the lateral branches 

 are set free and thereupon constitute new individuals ; secondly, by the 

 formation of small ovoid multicellular bodies (" brood-buds ") from single 

 epidermal cells of the prothallus, these becoming isolated by the rupture 

 of their pedicels ; thirdly, by the formation of thick-walled bodies con- 

 sisting of 'only a few cells, which probably are designed to undergo a period 

 of rest during an unfavourable season. Treub compared these two latter 

 kind of organs to the gemmae of the Hepaticae. 



On old or injured prothalli of L. Selago Bruchmann (1898, pp. 95-97) 

 found adventitious shoots on which rhizoids and sexual organs were de- 

 veloped, and which were able to live a separate existence when isolated 

 from the parent prothallus. 



