EXPERIMENTS IN HYBRIDISATION, &c. 99 
characters as carefully and minutely as a monographer would do, and in 
this way I have been able to follow the inheritance of specific characters 
much more easily than otherwise I could have hoped to do. In following 
out this idea I have chosen the orchideous genus Paphiopedilum (Pfitz), 
better known in gardens as Cypripedium, partly because hybridisation 
has been carried farther in this genus than in many others, and partly 
because I have the good fortune to have a large collection of living 
hybrids and their parents of this genus under my own observation from 
day to day. 
The limits of this paper will not allow fully detailed observations, but 
a few condensed analyses of some primary hybrid Paphiopedilums will 
well illustrate the inheritance of specific characters. In these cases 
practically the whole plant has been analysed from living specimens, 
twenty points in all being taken into consideration :— 
(1) The habit of growth; (2) the habit of flowering ; the form or 
shape of the (8) leaves, (4) scape, (5) bract, (6) ovary, (7) upper 
sepal, (8) lower sepal, (9) petals, (10) lip or slipper, (11) staminode ; 
the colour of the (12) leaves, (18) scape, (14) bract, (15) ovary, 
(16) upper sepal, (17) lower sepal, (18) petals, (19) lip or slipper, 
(20) staminode. 
Each of these parts or organs of the hybrid has been compared with 
the same part of each of the parent species. Each part is then classed 
in relation to the two parents, either (a) in the ratio as 1:1, which re- 
presents the part as fairly intermediate between the two parents; or (b) 
in the ratio as 3:2, which represents one parent to be slightly pre- 
dominant in that particular part; or (c) in the ratio as 2:1, showing the 
decided prepotency of one parent in that part; or (d) in the ratio as 3: 1, 
showing the very large prepotency of one parent in that part. In this 
way the twenty parts are classified, and when the various figures are 
added together one can see at a glance the total ratio of one parent to the 
other in the hybrid. In the following condensed analyses I have ignored, 
for the sake of simplicity, all the ratios as 1:1 and also those as 8: 2, 
classing them as intermediate or thereabouts, and only showing the 
undoubted prepotencies of either parent in the ratios as 2:1 and over. 
At the end of each are given the full ratios of the plant as a whole, as 
originally analysed, with the corresponding percentages of the predominant 
parent, for the sake of comparison. (For additional instances, see also 
under the heading of “ Variation of Primary Hybrids.’’) 
(1) Paphiopedilum x Winnianwm, a hybrid raised by Messrs. Veitch, 
of Chelsea, out of P. villosum (Pfitz) by P. Druryi (Pfitz). In form, the 
parent P. Druryi is prepotent in habit of growth, leaves, scape, and lower 
sepal; while P. villosum predominates in habit of flowering, petals, and 
staminode ; in all, favouring P. Druryi as 18:17. Jn colowr, P. Druryi 
preponderates in the leaves, lower sepal, and staminode ; while P. villosum 
prevails in the petals ; altogether favouring P. Druryi as 16:15. The 
whole plant in form and colour favouring P. Druryi as 34: 32, or 
51°5 per cent. 
(2) P. x Swinburnet, a hybrid raised by Messrs. Heath, of Cheltenham, 
out of P. insigne (Pfitz) by P. Argus (Pfitz). In form, the parent P. 
insigne is prepotent in bract, ovary, and upper sepal; while P. Argus 
H 2 
