fiO 
F.XIIimTTON MF.KTTNO, 1 f)o2 
subspecies. Silhouettes of radical and stem leaves showed the variation 
in leaf shape, size and degree of serration. 
The probability of the basis of 7*. flaminvht var. nvatus being gene- 
tical. and that of the small creeping form being ecological, was dis(‘ussed. 
Miss P. A. P.^DMORE. 
(4) rOA ANNUA and it.s P.^rents 
7'. annua L., like most common species, is very variable and con- 
sists oi a number of genetically distinct ecotypes. Three of these wei’o 
ex'hil)ited, one from light garden soil, one from a heavy wet clay and 
one from a stabilized dune. These differ strikingly in growth rate, 
size, hal)it and length of life. 
Artificial hybrids between P. nninin and the related diploids, P. 
infinna Kunth and P. sv'pina Schrad.. were shown. These hybrids 
are sterile but each shows 7 bivalents and 7 univalents at meioshs, 
indicating a high degree of homology between the chromosome set of 
P. annua and those of the diploids. 
Crossing the diploids yielded two plants with 2n=28; these have 
moi'phological characters of the same kind as fonnd in the wild P. 
annua l)ut do not exactly match any specimens that have been seen. 
Meiosis in the pollen mother-cells of these plants is regular, apart 
from the occasional formation of qnadrivalents, but the germination of 
the seed in preliminai-y trials was less than 10%. 
T. G. Tutin. 
(5) FJJPIIPARIA 17077 77.97/ axo E. MICPANTTIA x ANGLIC A 
I'j. viifursii Davey was considered by I’ugsley to be a hybrid be- 
tween E. micra ntha Reichb. and E. anglica Pugsl. At Roborough 
Down, near Plymouth, it occxirs with E. anqlica and a form of E. 
ntanorosa. (Pers.) H. Mart. Specimens of these plants were exhibited, 
with notes on their ecology and distribution. E. vigursH has a dis- 
tinct habitat and I'ai-ely mixes with the other forms. In the locality 
where the othei' two foims mix, no ajiparent hybrid could be found at 
Ibis local it.y in 1952. 
E. vifpirsli has a chromosome number of 2n = 22; E. atiglica 
(New Forest and Charnwood Forest) 2n = 22, and E. nemnrosa (North- 
ants) 2n = 44. 
P. F. Yfx). 
CALEOPSIS TETPAHIT and G. BIFIDA 
A number of s])ecimens of G. fp.trahit L. and G. bifida Roenn. from 
the Druce Herbarium were scored for a number of characters, particu- 
larly those used by various floras to separate the two species. Drawings 
of the flowers were also shown, and some ‘typical’ G. tetrahit and G. 
bifida were exhibited, together wdth a selection of intermediate types. 
In an attempt to separate the two species some of the characters for 
which they had been scored were plotted as graphs, two of which (leaf 
