210 SUMMARY' OF CURRENT RESEARCHES RELATING TO 



for the genus. The fact that the protocomious species belong to two 

 groups in the sub-genus Rhopalostachya suggests a certain degree of 

 antiquity for the protocorm within the genus Lycopodiimi ; and, if the 

 cernuwn type of prothalhis be primitive, would suggest that Rhopalo- 

 stachya comprises the more primitive Lycopodiaceae, and that the genus 

 as a whole should be regarded as a reduction series rather than as a 

 series which has progressed from those which show the simpler type of 

 sporophyte. 



Prothallium of Lycopodium.* — K. V. Edgerley gives the result of her 

 investigation of the prothallia of three New Zealand species of Lyco- 

 podium : — 1. Spores of L. BiJIardieri and L. novae-zelandicum do not 

 germinate readily. 2. Prothallia of L. volubile and L. scariosam resemble 

 one another externally. Both are colourless and saprophytic, but that of 

 L. roluhih may come above the surface, and it is smaller. Prothallia 

 of L. Billardieri and other epiphytic species resemble those of L. phleg- 

 maria. 3. As to structure of prothallia, L. volubile and L. scariosum 

 resemble L. clarafum, but L. scariosum has but one-sixth of its tissue 

 infected with fungus. L. scariosum resembles both L. clavalam and 

 L. annotimm. in having a single row of cells elongated at right angles 

 to the surface on the prothallium, and having the fungus intracellular. 

 This layer is absent in L. volubile. In L. Billardieri there is a close 

 resemblance to L. phlegmaria, but no pits were seen in the Avails of the 

 elongated central cells, though in the walls of the peripheral layer the 

 pits were very conspicuous. 4. Starch was abundant in both L. volubile 

 and L. scariosum in the parenchymatous storage layer ; and in L. 

 scariosum the walls of the cells l)elow stained liglit-blue with iodine, as 

 if the fungus filaments in the wall contain starch. 5. Fungus was 

 present in all three species, L. volubile, scariosum and Billardieri. In 

 the first the fungus does not enter the rhizoids, but pierces the wall of 

 the basal cell of the rhizoid and so comes into contact with the humus ; 

 while in L. scariosum the hyphae are found also in the cavities of the 

 rhizoids. C. As to reproductive organs — antheridia in all three species 

 were of the usual Lycopodiaceous type, those in L. volubile projecting 

 a little above the surface, while those in L. scariosum and L. Billardieri 

 were completely sunk in the prothallium. The archegonial develop- 

 ment is also normal, but for variation in numlier of the neck-canal cells 

 — four to seven in L. volubile, six in L. scariosum, five in L. Billardieri. 

 The paraphyses of L. Billardieri are composed of fewer cells than in 

 L. Selago and L. phlegmaria, and are usually . unbranched. 7. The 

 embryology was not traced in detail ; but the embryos of L. volubile and 

 L. scariosum are undoubtedly of the L. clavatum type. There is a 

 larger persistent foot and no sign of a protocorm. In L. Billardieri the 

 foot is fairly large arid persistent. 



* Trans. Proc. New Zealand Inst., xlvii. (1915) pp. 94-111 (figs.). 



