Observations on the Anatomy of Teratological 
Seedlings. 
I. On the Anatomy of some Polycotylous Seedlings of 
Cheiranthus Cheiri. 
BY 
H. S. HOLDEN, M.Sc., F.L.S., 
Bacteriologist ( Temporary ), R.N. Hospital, Plymouth, 
AND 
DOROTHY BEXON, B.Sc., 
Late Research Scholar in Botany , University College, Nottingham. 
With seventeen Figures in the Text. 
HE discovery by one of us of a strain of wallflower which threw 
Jl a considerable percentage of abnormal seedlings seemed to offer 
a favourable opportunity for an anatomical study of specific teratological 
polycotyly on a somewhat more extensive scale than had hitherto been 
possible. 
The particular strain of Cheiranthus , in addition to producing all 
types of seedling from the tetracotylous to the normal dicotylous form, 
exhibited a number of other features of some interest. Among these may 
be mentioned an alteration in the time of flowering, the production of 
a rather delicate seedling as compared with more normal strains, and also 
a relatively high percentage of abortive seeds. Thus in a total sowing of 
212 seeds, there were 123 failures, 56 normal seedlings, and 33 abnormal 
ones. 
The number of abnormal seedlings obtained from this source was 
augmented by the collection of some specimens from a common garden 
variety, most of these apparently throwing a few polycotyls. 
The total number of polycotylous seedlings examined was fifty-four, 
and these fell into the following groups, as far as one could judge from 
external characters: 
Type of Seedling. 
A 7 o. of Seedlings. 
Hemitricotyls 
Tricotyls 
Hemitetracotyls 
Tetracotyls 
9 
* 32 
12 
[Annals of Botany, Vol. XXXII. No. CXXVIII. October, 19x8.] 
