64 
THE ORCHID WORLD. 
[December, igi2. 
results. Experiments are yet wanting to pro- 
vide breeders with a complete analysis of the 
germinal constitution of all the well-known 
albinos, and this cannot be satisfactorily 
accomplished until we can be quite certain as 
to the identification of individual albino 
plants, and, more important still, that the 
albinos concerned are true albinos. 
In working with albinos Orchid breeders 
must be careful to distinguish between true 
albinos and false albinos. True albinos have 
pure white flowers and green leaves without 
a trace of purple sap-colour, though yellow 
plastids are usually present in the flowers. 
As we have seen, one or both of the colour 
factors C and R are absent in the germ-cells 
of these forms. On the other hand, false 
albinos, like Cypripedium insigne Sanderae, 
C. Lawrenceanum Gratrixianum, Cattleya 
Mossiae Reineckiana, and others, have a cer- 
tain amount of purple sap-colour in the 
flowers and leaves, and, consequently, are not 
true albinos, though for practical purposes 
they are usually called" albinos," and in many 
cases are quite as beautiful and as much 
sought after as the true albinos. In these 
false albinos both the colour factors C and R 
are present in the germ-cells, and conse- 
quently they give quite different results in 
breeding from the true albinos. These false 
albinos are really dilute coloured forms, and 
the fact that they usually behave as Men- 
delian recessives in breeding shows that their 
condition is due to the absence of a factor for 
dense or full coloration, which factor is 
present in the tyjMcal coloured form. 
The different kinds of dilution found in 
most species suggest that more than one 
factor is concerned in the typical dense form. 
This app'ication of genetics to Orchid breed- 
ing explains a good many apparent mysteries. 
For instance, it explains why the false albino 
Cypripedium insigne Sanderas breeds true 
to its special dilute form or throws true 
albinos when selfed, and yet behaves as if it 
were an ordinary C. insigne when crossed 
with the true albinos C. Maudia?, C. Law- 
renceanum Hyeanum and C. callosum San- 
derae. These true albinos arose originally by 
the loss of a colour factor (C), but the factor 
for dense coloration (D) would still be 
present in those albinos though not mani- 
fested on account of the albinism. When 
this factor for dense coloration (D) is brought 
in b)' the cross it naturally causes the parent 
C. insigne Sanderje to behave as if it were an 
ordinary C. insigne. 
If these so-called " reversionary " forms 
were to be self fertilised or crossed inter se, 
both the recessive dilute coloration (dd) and 
the albinism (cc) would appear in certain 
individuals. On the average the dilute forms 
would be expected to appear in three out of 
sixteen plants, and the albino forms in four 
out of sixteen plants. The recent cases 
reported in which the true albino Cypri- 
pedium Lawrenceanum Hyeanum crossed 
with the false albino C. niveum gave typical 
coloured plants of C. Aphrodite, and in which 
the false albino C. niveum crossed with the 
false albino C. Lawrenceanum Gratrixianum 
gave the false albino C. Antigone album are, 
of course, easily explained in the same way. 
(To be con/inued. ) 
BRUSSELS SHOW. 
At the recent Orchid Show held in the 
Salle de la Madeline, Brussels, Mons. F. 
Lambeau obtained a Gold Medal, value 
300 fr., for the best group of species and 
hybrids, and a Silver-gilt Medal for the best 
hybrid ; Mons. Ch. Dietrich received a Gold 
Medal fo"" the finest 100 Orchids, and a 
Diploma of Merit for the best single speci- 
men ; Mons. Jules Hye de Crom was awarded 
a Silver-gilt Medal for some very fine 
Cattleya hybrids ; Mons. Th. Pauwels and 
Co. obtained a Gold Medal for a large group 
of Orchids, and a similar prize for the best 
25 species ; Messrs. Duchesne and Lanthoine 
received a Gold Medal for an extensive 
group ; Messrs. Peeters and Sons were 
awarded a Gold Medal for a fine group of 
Cattleyas ; Messrs. Chailcsworth and Co. 
received a Silver-gilt Med.il for an interesting 
group ; Mons. Ch. ]\Iaron was awarded a 
Silver-gilt Medal for the best group of 20 
plants, and a similar award for a collection of 
wliite Cattic\as. 
