In this state, therefore, it offers a marked excep- tion to the law which is so prevalent among monocotyledons, " that the number 3, or a multiple of it, should prevail in the developement of some part or other of their structure The frequency, however, with which this plant deviates from its more common condition, seems to indicate a great degree of instability in the operation of whatever be the law which regulates the developement of its subordinate parts; which should make us cautious in pronouncing upon the normal condition of its several foliaceous whorls.

It seems to me that some light may be thrown upon this question by examining a great number of specimens from different localities, and recording the limits within which the number of parts in each organ is found to vary.

With this view, I have, for the last three or four years, noted the different varieties gathered by myself and two friends, Messrs.

Babing- ton and Downes, in a habitat near Cambridge.

The result of our examinations, made upon 1500 specimens, I have arranged in the following tables, upon which I shall offer a iew remarks.