226 Mr, Masters, an the Relation between the [March 16, 



all five sepals are green, and of equal size. We can hardly consider a 

 return to regularity, in whatever way it be effected, as anomalous ; and 

 it has been before shown that irregular flowers are not necessarily 

 monstrous. It is not requisite to go through the classification of M. 

 Moquin Tandon, at any greater length, as the same remarks, to a 

 greater or lesser extent, apply to all the groups. 



As confessedly artificial distinctions, it may be said that a variety 

 is some change from the ordinary condition of a plant — a change in 

 nowise impairing the exercise of the physiological functions — a change 

 affecting the whole, or at least several parts of the plant, — a 

 change which is more or less constant and permanent and which is 

 reproduced. On the other hand, in a monstrosity, there is a change 

 which does more or less interfere with the due exercise of the functions 

 of the organs affected — a change usually affecting one organ, or one set 

 of organs in a plant, — a change, less constant and permanent than in a 

 variety, — a change which is rarely reproduced. 



Allusion was then made to the value of Teratology, as affording 

 the basis on which the now generally received theory of vegetable 

 morphology rests. No doubt the unusual conditions of plants, whether 

 they be called varieties or monstrosities, arise frequently from the 

 operation of that ceaseless struggle for existence in the battle of life, to 

 which Mr. Darwin, as well as the late Dean Herbert attribute so much 

 importance ; but we should be extremely careful in reasoning from 

 malformations, and even from varieties, either in support of, or in 

 opposition to Mr. Darwin's views, especially if the word species be 

 understood in its widest acceptation. The amount of change, great as 

 it is in certain instances, is not greater than is the diversity of form 

 under which the same individual plant may occur : moreover, the 

 changes on which Mr. Darwin relies are small in degree, but constantly 

 increasing. Violent and sudden changes are disavowed by him ; for 

 though the result of a struggle for life, yet they tend rather to the 

 extinction of the organ or of the plant, than to the production of a new 

 species. If Mr. Darwin's views be pushed to their fullest con- 

 sequences, it would appear as if there were no limits to variation ; and 

 it is of the highest importance to ascertain whether this be so or not. 

 Without forgetting the necessity of caution in employing' teratological 

 facts in such a question, the speaker cited as tending to show the pro- 

 bability that there were limits to variation, the fact that in the malfor- 

 mations of what are considered to be the most highly specialized groups 

 of plants, those whose structure is most complex, most concentrated, and 

 furthest removed from the leaf type, as Compositce, Umhelliferce, &c., 

 little or no exaltation of the type ever occurs, whereas in other orders 

 whose structure does not so widely depart from the leaf type, such an 

 exaltation is frequent, though always less so than the opposite process 

 of degeneration. 



The degree of constancy is very various, and most important to be 

 considered in questions of this kind. The speaker is under obligations 

 to his father for the following interesting facts bearing on this point. 



