108 



PRINCIPLES OF PLANT-TERATOLOGY. 



encroached ever more nearly to the apex until it has 

 entirely usurped it. No interpretation of this sort 

 can be placed on the phenomena in Selaginella above 

 described. My observations seem to prove unequivo- 

 cally that the normal rhizophore has the morpholo- 

 gical value of a shoot." (For further details and 

 remarks on this subject the reader is referred to this 

 memoir.*) 



2. Axillary. — Some individuals amongst plants 

 which as a rule produce no shoots in the axils of 

 certain of their leaves are observed to form them more 

 or less abundantly. 



Referring firstly to the Dicotyledons, there is an 

 interesting example of this in the foxglove (Digitalis 

 purpurea), all parts of which were more or less vires- 

 cent. In the axils of all the foliage-leaves on the 

 flowering-stem were short leaf -bearing shoots, in 

 correlation with which character the main axis was 

 abnormally low in stature. 



It sometimes happens that the potato bears tubers 

 in the axils of the foliage-leaves, whereas normally 

 they occur in the axils of scale-leaves on the subter- 

 ranean shoot. 



In the 6 Gardeners' Chronicle ' of 25th October, 

 1856, is figured a broccoli (Brassica oleracea var. 

 botrytis) with six perfect heads on one stalk. 



Long ago Sachs made some interesting experiments 

 with seedlings of the scarlet runner (Pliaseolus multi- 

 florus). The writer has lately repeated these with 

 similar results. At a very early period, viz., before 

 the plumule had emerged from between the hypogseal 

 cotyledons, it was excised ; this had the result in a 

 large percentage of seedlings, although not in all, of 

 causing strongly-fasciated shoots to grow out from the 

 axils of (usually) both cotyledons, where normally, if 

 the plumule had developed, no such axillary shoots 

 occur, or only in the form of small, undeveloped buds 

 (fig. 27, p. 96). Hence this is a good instance of 



* Worsdell, c New Phytologist/ vol. ix (1910), pp 242-249. 



