REPORT OF THE CONFERENCE ON GENETICS. 30 
To show results obtained in a case where the parents differ as regards 
two features (surface character and flower-colour), which are dependent 
on the inter-relationships of several factors. 
5. Ranunculus arvensis (a) type, (6) tuberculatus, (c) inermis. 
A case where prickliness in the fruit is dominant over the unarmed or 
partially armed condition. 
6. Mercurialis annua. 
A case where parthenogenetically developed individuals are all female. 
* * * # * * 
ExuHIpit oF EXPERIMENTS IN CROSS-FERTILISATION OF VARIETIES OF 
ANTIRRHINUM MAJUS BY Miss M. WHELDALE, Newnham College, 
Cambridge. 
The experiments were made with a view to investigating the laws of 
inheritance of the flower-colour. Specimens were shown of the types of 
tke original parents and of those occurring in the first and second 
generations from some dozen or more crosses. 
The various colours exhibited by the corolla are due to various com- 
binations of several pairs of Mendelian characters, and the proportions in 
which the types appear experimentally have been found to agree closely 
with the proportions calculated theoretically. 
PLANTS AND SEEDS EXHIBITED By R. H. Lock, Caius College, Cambridge. 
1. Pea plants illustrating the characters used by Mendel in the 
original experiments which led to the discovery of his law. 
2. Specimens illustrating the inheritance of the colour of the testa of 
peas. Three pairs of allelomorphs are concerned : 
The presence and absence of a grey colour, C and ¢ 
The presence and absence of purple spots, P and p 
The presence and absence of “ maple’’ marks, M and m 
P and M only lead to the development of a visible character when they 
occur in the same zygote with C. 
3. Seeds of Canavalia ensiformis. A large number of new types 
appeared in F, from the cross red » white. The inheritance of these has 
not yet been worked out. 
4. Specimens of maize illustrating Mendel’s laws of inheritance. The 
majority of specimens show the result of crossing the crossbred form 
(heterozygote) with one of the parents (recessive). In most cases the two 
parental types of grain make their appearance in equal numbers under 
these circumstances. 
* ¥ = 
% *€ : * *€ x * 
ExHisit oF Hysprip WHEATS AND BarRteys By R. H. BIFFEN. 
Beardless x Bearded Wheat. 
F,. Beardless. 
F,. Beardless : Bearded :: 3: 1. 
F;. Beardless breeds true once in three times, bearded always. 
Cc 
