100 



Transaction) 



They have also relatively larger nuclei and more abundant cell-contents. 

 There was no sign of a protocorm. The tissue of the prothallium below the 

 foot consists of rather flattened cells, in which starch is present. Examina- 



Fig. 14. — Foot of same, more highly magnified, 

 showing the limiting layer of cells. X 267. 



tion of several voung sporophytes proved that the vascular bundle does not 

 extend into the foot. It is quite clear that the embryo of L. volubile is of 

 the L. clavatum-annotinum type. 



Lycopodium scariosum. 



The prothallia of L. scariosum are, according to Mr. Holloway, always 

 subterranean, being deeply buried (4-6 cm.). Like L. volubile, the pro- 

 thallium of L. scariosum resembles that of L. clavatum, but it is even larger 

 than that of L. volubile. The largest specimen cut was 14 mm. by 9 mm. The 

 prothallia were conical below, becoming cylindrical above (figs. 15 and 16). 

 The upper surface of the prothallium is concave, lighter in colour, devoid 



Figs. 15, 16. — Prothallia of L. scariosum. X 3. 

 Fig. 17. — View from above of prothallium. rd, reproductive 

 ridge. X 6. 



of rhizoids, and with a ridge running round the margin, on the inner surface 

 of which the sexual organs are found. In other cases— e.g., fig. 17- — two 

 ridges have been formed, one towards the centre of the prothallium and the 

 other round the margin. The prothallium mentioned above as the largest 

 was quite differ nt in shape (fig. 15). it was obtuse-angled below, and the 

 whole surface very much lobed and wrinkled. 



