Observations on the Anatomy of Teratological 
Seedlings. 
II. On the Anatomy of some Polycotylous Seedlings of 
Centranthus ruber. 
BY 
DOROTHY BEXON, M.Sc., 
University College , Nottingham . 
With nine Figures in the Text. 
T HE following study of polycotylous seedlings of Centranthus ruber was 
carried out in the hope of discovering, amongst the abundant material 
offered by this species, evidence corroborative of and supplementary to that 
obtained in the investigation of Cheiranthus Cheiri (9) as to the origin of 
polycotyly. 
Centranthus ruber apparently yields a fairly high proportion of poly- 
cotylous seedlings, amongst which all the usual types of abnormality are 
included. Thus from about two square yards of soil on which self-sown seeds 
of Centranthus were germinating, a large number of polycotylous speci- 
mens were gathered, of which eighty-seven seedlings have been examined, 
these grouping themselves according to external characters as .follows : 
Type of Seedling . 
Hemitricotyls 
Tricotyls 
Hemitetracotyls 
Tetracotyls 
Trisyncotyls 
Number of speci- 
mens examined. 
39 
38 
5 
4 
1 
Structure of the Normal Seedling. 
Centranthus ruber has not apparently received any attention previously 
from the point of view of seedling anatomy, so that a short description of 
the normal seedling will not be out of place here. 
The seedling is fairly robust, being usually from six to eight centi- 
metres in length, whilst the cotyledons are of medium size, and are shortly 
petiolate. There is a slight tendency observable towards the formation of 
[Annals of Botany, Vol. XXXIV. No. CXXXXII. January, ig&o.] 
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