HoLLOWAT. — Studies in the New Zealand Species of Lycopodium. 215 



General Form of the Prothallus. 



L. cernuum. — The typical prothallus of L. cernuum consists, according 

 to Treub, of a basal " primary tubercle,'' a longer or shorter shaft, and 

 a crown of lobes, immediately beneath which lies the meristem and the 

 sexual organs. The prothallus is radial in build, erect in growth, and 

 situated at the surface of the soil, being gTeen in its lobes and in the upper 

 portion of the shaft. It is the most delicate and the smallest of all the 

 types of Lycopodium prothalli, the allied L, salakense possessing a still more 



43 



Fig. 42. — L. cernuum. Longitudinal section of prothallus of intermediate length, x 50. 

 Fig. 43. — L. cernuum. Longitudinal section of basal fungal region of prothallus, 



showing lateral extension, x 50. 

 Fig. 44. — L. cernuum. Longitudinal section of prothallus of thick, short form, x 32. 

 Fig. 45. — L. cernuum. Longitudinal section of meristematic region of prothallus, with 



a fertilized archegonium. x 50. 



filamentous prothallus. Some of the prothalli of this species which I have 

 found are comparatively long (7, fig. 17, and fig. 38 in the present paper). 

 That shown in the latter of these two illustrations was broken at its upper 

 extremity, so that I do not know its complete length. In others, again, the 

 shaft is short and thick, and the general appearance of the prothallus more 

 massive (7, fig. 20, and figs. 40 and 44 in the present paper). Forms of inter- 

 mediate length are shown in a previous paper (7, figs. 18, 19, and 21) and 

 in fig. 42 of the present paper. I have also found a considerable amount 

 of variation in the distribution of the fungus, and, since the fungal regions 

 are always more or less swollen, there is a corresponding variation in the 



