640 DR DICKSON ON DEVELOPMENT OF 



expanded outer leaves of the autumn rosette disappear ; the central portion 

 remaining as a firm, bulb-like, winter-resting bud, the outer leaves of which are 

 developed as somewhat fleshy scales. This bulb-like bud remains during the 

 winter sunk in the soil, or among the surrounding moss ; and, on the return of 

 warm weather the next season, expands into the summer-rosette, terminated by 

 the inflorescence as above described. 



Rudiment of the Inflorescence in Winter-Bud. 



On removing the leaves from the winter-resting bud, the following struc- 

 tures appear : — 1st, A cushion-like mass in the axil of the last leaf, the rudiment 

 of the bud which developes the autumn-rosette of the next season, and becomes 

 the flowering plant of the summer thereafter. This cushion usually (always ? ) 

 appears somewhat depressed, in a direction corresponding to the middle line of 

 the supporting leaf, as I have indicated in Plate XXVIII. fig. 1 ; but as to the 

 significance of this median furrow, I am unable to offer any suggestion. 2d, The 

 termination of the main axis, which appears as an unequally three-sided cushion, 

 nearly flat on the top, and with rounded angles, the largest and thickest of which 

 represents the rudiment of the first flower, the angle next in size representing 

 that of the second flower, and the remaining angle (often very obscure) that of 

 the third flower. 



These floral rudiments continue, as to position, the spiral succession of the 

 leaves upon the main axis. If a number of plants be examined, the spiral will 

 be found running sometimes to the right, and sometimes to the left, in about 

 equal proportions (see figs. 1, 2, 3, 4, 5, and 9). The fraction expressing the leaf- 

 arrangement appears to be ^ approximately ; and the spiral succession of leaves 

 developed upon the axillary shoot of the last leaf is homodromous with that 

 of the main axis. 



Early Obliquity of the Floral Axis. 



Almost as soon as the young flower has begun distinctly to project from the 

 axis of inflorescence, and before there is any appearance of sepals or other floral 

 parts, it is seen to be more developed on the anterior aspect (that furthest from 

 the axis of inflorescence) than on the posterior. At this stage the young flower 

 appears as a short cylindrical body, the free extremity of which is flattened in a 

 direction from above anteriorly, downwards posteriorly (see Plate XXVIII. fig. 2). 

 This very early indication of irregularity is noteworthy, from the circumstance 

 that, as a rule, irregularity commences to show itself only with, or shortly after, 

 the appearance of the appendicular organs. 



Calyx. 

 The sepals make their appearance a little below the obliquely flattened 



