478 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY, 



variegated fronds (green with white stripes), which every year produces 

 in my fernery abundant offspring with every frond, even the first, 

 variegated like the parent. 



On the other hand, there is no evidence, so far as I am aware, that a 

 self-fertilised albino has ever produced coloured offspring. 



The term " albinism " may very well be restricted to the case of floral 

 organs, and four forms of it may be distinguished : 



1. Incomplete Albinism, when the intensity of the floral colour is 

 diminished although the plant may be healthy and in vigorous growth. 

 This is very common, and everyone knows these pale and washed-out 

 forms. 



2. Complete Albinism, when the colour disappears entirely from a 

 flower, leaving it all white. Coelogyne cristata alba, Cattleya intermedia 

 alba, and many other examples are well known. 



3. Partial Albinism, when one colour completely disappears from the 

 floral envelope, leaving an underlying or overlying colour in full or 

 diminished strength. Thus the dull brown colour of Cypripedium insigne is 

 caused by purplish-red cell- sap in the epidermal cells overlying greenish- 

 yellow chromoplasts in the deeper cells. In the sport C. insigne Sanderce 

 the reddish cyanin (red-blue pigment of the cyanic series) has entirely disap- 

 peared from all parts of the flower except the dorsal sepal, where a little 

 is found, leaving the yellow or greenish-yellow pigment (of the xanthic 

 series) to show alone. In Odontoglossum luteo-purpurcum, as in many 

 other Odontoglossums, the rich chocolate markings are caused by a cyanic 

 pigment overlying a xanthic. In the form 0. luteo-purpureum sceptrum 

 the cyanin has disappeared and the flower is all yellow. In 0. crispum 

 xanthotes, Cypripedium insigne Sanderianum, C. callosum Sanderce, and 

 C. Laivrenceanum Hyeanum, we get similar results by the suppression of 

 the surface colour. The orange-red colour of Sophronitis grandiflora is 

 produced by a red cell-sap in its epidermal cells, which also contain yellow 

 chromoplasts lying along their inner walls. When one or the other of 

 these colours defaults we shall get a bright crimson or a yellow S. grandi- 

 flora. 



It is rarer for the underlying colour to be wanting. In some colour- 

 varieties of Odontoglossum crispum the xanthic pigment has failed, or 

 nearly so, and the large blotches on the flower show a magnificent purple- 

 red or deep crimson. 



4. Local Albinism, when the colour completely disappears from a 

 portion of the flower, leaving that part quite white. The albino form of 

 Lcelia anceps is an example of this. The violet-red colour of the flower 

 is suppressed, but the palate is still deep yellow. 



It is obvious that there may be combinations of these forms of 

 albinism. Thus a flower may exhibit partial albinism locally, or incom- 

 plete albinism partially. 



An example of local albinism occurs in the Shirley Poppy, and as 

 there are unusual and interesting features in connection with these 

 flowers, and their history is so well known to their selector, whilst their 

 development has been so carefully guarded for nearly a quarter of a 

 century, 1 have; thought it would be as well to lay it before the members 

 of the Scientific Committee. For the history of these flowers I am 



