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Transactions. 



plant becomes somewhat spindly in form. Abundant starch commonlv 

 occurred in the plants both in the tuberous region and in the rhizoids. 



The old roots on which these plantlets were borne were frequently seen 

 to be green, and even vividly green, in isolated patches, especially in the 

 neighbourhood of the attached plants. Where a young plant was torn 

 away from a root by brushing, a gaping hole was left in the latter, showing 

 that tiie plant had taken its origin in the interior of the root and had had 

 to emerge through a split in its external tissues. It was observed that at 

 the point where a young plant was attached a group of rhizoids was present, 

 and these rhizoids were found to be developed not from the plant but from 

 the epidermal cells of the root. Plantlets at a somewhat later stage, and 

 those detached from the parent roots, showed rhizoids on their basal por- 

 tions. Isolated plantlets in a few instances were seen to show fragments 

 of torn parenchymatous tissue attached to the basal region at one point 

 or other. This would probably represent the remains of the cortical tissues 



Figs. 6-10. — Lycopodium ramulosum. Gemmae developed from cortical cells of old 

 isolated rootlets. Figs. 6 and 10 X 100 ; figs. 7, 8, and 9 X 120. 



of the parent root. The first-formed end of the tuber of some of the plantlets 

 was of irregular form, the superficial cells growing out, or one or more 

 haustoria-like prolongations of the tuber being developed. Probably this 

 is to be put in connection with the nutrition of the developing plant from 

 the root-tissues. 



It commonly was the case that several plantlets in different stages of 

 development were borne at the same spot on the root (fig. 13, and Plate VIII, 

 fig. 2). In one instance I noticed, before dissecting out a certain piece of 

 mossy turf, that three groups of protophylls were showing above the sur- 

 face of the moss at distances of about a quarter of an inch from each other, 

 and all in a straight line. These groups were foimd to be connected by an 

 old root. In each group were well-grown young plants, as well as a large 

 number of plantlets of all ages, some separate and others attached to the 

 old root or to its various branches. All the individuals in these three groups 

 had probably arisen adventitiously. 



