Anatomy of Teratological Seedlings. /. 529 
sub-tribe Robiniinae [( 3 ) pp. 41-5], to which Carmichaelia australis 
belongs. In view of these facts it seems reasonable to suppose that the 
robust strand of the new cotyledon would supplant the feeble pole derived 
from the laterals. 
It has not been felt to be necessary to deal with the class of cotyledons 
termed ‘subsidiary’ by Hill and de Fraine since, they have no bearing on 
our work. This group is left in rather an ill-defined condition, and seems 
to contain all cases which cannot be definitely classed as ‘ whole ’ or half 
cotyledons. Although they do not make any definite statement it is 
evident that they include in this class at least two types of cotyledon : 
(a) displaced foliage leaves ; 
(b) cotyledons formed by the splitting off of tissues laterally from the 
normal cotyledon, the splitting being either symmetrical or asym¬ 
metrical. 
The variety of behaviour, however, is so great, and the number of 
seedlings of each species examined is relatively so small, that on the present 
evidence it seems impossible to put forward any comprehensive explanation 
of the phenomena found in these seedlings. A more thorough investigation 
of two or three species seems to be called for, and such an investigation is 
now in progress. 
Summary. 
1. The vascular anatomy of a series of wallflower seedlings showing 
cotyledonary abnormality ranging from hemitricotyly to tetracotyly is 
described. 
2. This is believed by us to indicate at least two, and possibly three, 
methods of cotyledonary increase : 
(1) By cotyledonary fission ; 
(2) By dichotomy of the growing point of the cotyledon ; and 
(3) Much more doubtfully, by the downward displacement of one or 
more epicotyledonary leaves. 
3. It is finally shown that previous work on schizocotyly is capable of 
interpretation on this basis, and affords illustrations of all these types of 
increase. 
The authors are much indebted to Dr. T. G. Hill for his courteous 
permission to examine a number of slides of Gymnosperm seedlings, and 
also to Professor Carr, University College, Nottingham, who granted every 
facility for the investigation. 
