228 THE ORCHID REVIEW. [AuGuSst, 1908. 
the species which grow intermixed are cross-fertilised by insects, and that 
the hybrids are completely fertile. Approximately parallel cases were now 
known among artificial hybrids, particularly of O. Harryanum. The absence 
of similar variation where O. crispum was found by itself might be taken as 
to a certain extent confirmatory evidence. Natural hybrids were found in- 
several other regions, and our knowledge of them was almost entirely due 
to the popularity of the species with which they are found as garden plants, 
and the numbers in which the latter are imported, this applying with special 
force to the popular O. crispum. Without such popularity our knowledge 
of the subject would have been practically nil. It was believed that the 
facts could be paralleled in the genera Salix, Rosa, Rubus, and various 
others, if their history could be investigated in the same way. 
The subject was worthy of increased attention, for it was admitted that 
crossing increases variability, and variation is the material on which natural 
selection works. Many hybrids were completely fertile, and spontaneous 
hybrids often possessed such distinctive features as to have been described 
as new species or as varieties of one or the other parent. Their permanence 
was a matter for further study and experiment. Crossing might lead to or 
hasten the appearance of distinct races, for there were many races of 
“ florist’s flowers” and other garden plants which were known to be of 
mixed origin. Thus hybridisation was a question of great biological 
importance, and one which had to be taken into account in discussing the 
very origin of species, indeed it was probably of more importance than had 
yet been realised. 
INHERITANCE OF ALBINISM IN ORCHIDS. 
_ FLowers of two interesting hybrids of Paphiopedilum insigne Sandere are 
sent from the collection of Max Isaac, Esq., Wildecroft, Blundellsands, 
near Liverpool (gr. Mr. Driver), which supplement the information given 
under the above heading (pp. 58, 103, 106). In one case the pollen parent 
was P. Lawrenceanum Hyeanum, and in the other P. X Mandiz, and Mr. 
Driver remarks that both were expected to yield albinos, instead of which | 
they have gone back almost to ordinary coloured forms. They are thus 
parallel to the cases previously recorded. 
The hybrid between the ordinary P. insigne and P. Lawrenceanum is P. 
x Eucharis, and as their albino varieties come true from self-fertilised seed, 
it might have been anticipated that these latter when intercrossed would 
produce an albino hybrid—at all events at the time when the cross was 
made. Instead of this only a light-coloured form of P. x Eucharis is produced. 
P. insigne Sandere crossed with the albino P. callosum Sandere, 
yielded a light-coloured form of P. x Leonez, instead of an albino, as was 
previously recorded. 
