364 STUDIES IN SEEDS AND FRUITS 



out that this would not follow if we accept the standpoint 

 taken by Dr Goebel in his Qrganography of Plants (i. 61), that 

 functionless organs in plants are not necessarily the vestiges 

 of former completely developed ones, and that many more 

 primordia are laid down than become functional. 



Many points remain to be determined before we can safely 

 generalise in these matters. It is of importance, for instance, 

 to ascertain by microscopical examination why, with the same 

 complement of about twelve ovules in the flower, ten or eleven 

 seeds are matured in Vicia sativa and only half that number in 

 Vicia sepium. Then, again, it would be necessary to learn if 

 the ovules that fail in the acorn, coco-nut, and similar fruits, 

 have the same microscopical characters as the ovules that com- 

 plete their development. 



Some indica- Nearly all the data included in the following table are from 

 following my own observations, with the chief exception of those relating 

 table. to Convallaria, which are taken from Lord Avebury's book on 



seedlings. Although with many-ovuled flowers there is great 

 variation as to the number of ovules that mature as seeds, as 

 many as 80 or 90 per cent, failing in Ravenala and as few as 

 17 per cent, in Aquilegia and Lychnis^ yet a rough average 

 shapes itself for several of the capsules here dealt with. Thus 

 with Iris, Primula^ Scilla^ Stellaria, and Arenaria about two-thirds 

 of the ovules mature as seeds, and of the remainder the greater 

 number (about 25 per cent, of the ovular complement) abort 

 soon after fertilisation, whilst the residue advance a little in 

 their growth and fail as young seeds. With leguminous 

 plants the same rule prevails, though the data are insufficient 

 for a numerical statement. Here also a large proportion of 

 the ovules develop into seeds, but a considerable number fail, 

 and of the failures most are concerned with the abortion of 

 the ovule soon after fertilisation. 



In nearly every case the number of the ovules in the flower 

 has been directly determined ; but in the cases of Ravenala 

 and Opuntia it has been estimated from the total of mature 

 seeds and of seed-failures. 



