558 MR. W. B. HEMSLEY ON THE GERMINATION 
I can only suggest that in a cluster of seedlings there is a 
greater chance of partial escape from phytophagous organisms 
of various kinds than there is for solitary individuals; but I am 
aware that this suggestion is open to numerous objections. 
Taking our native trees for comparison : they have mostly either 
solitary seeds, as in the oak; or, if there are several, they are 
furnished with some appendage that facilitates dispersal, as the 
comose seeds of the willow. 
Another interesting point is the presence of buds in the axils 
of the cotyledonary leaves of Davidia. The advantage of 
cotyledonary buds is probably this, as in many other instances, 
that if the plumule is injured or destroyed the development of 
the plant is continued by them. But this is not always the case, 
as is shown by Gustav Kock in ‘ Oesterreichische Botanische 
Zeitschrift,’ liii. p. 58, who there gives the results of the 
investigation by himself and others of seedlings of 152 different 
plants belonging to 49 different natural orders. In Dianthus 
Caryophyllus the cotyledonary buds develop simultaneously with 
the plumule. In Nasturtium officinale they grow into roots. In 
TLrapa natans they form shoots which soon detach themselves 
and become independent plants. In Ulex they grow into 
thornless branches. In Lathyrus tuberosus they grow out as 
runners. In many species of Linum the plant becomes perennial 
through their development after the primary stem has died down. 
In Thesium montanum only the cotyledonary shoots bear flowers. 
And in Scrophularia Ehrharti they grow during the summer 
and autumn into short-jointed shoots which strike root and grow 
out the following spring. 
Davidia was discovered by the Abbé David near Moupin in the 
Province of Szechuen, and apparently only in small quantity. It 
was described by the late Dr. H. Baillon (‘ Adansonia,’ x. p. 114) 
in 1871, from flowering specimens. In 1889 Dr. A. Henry 
sent a fruiting specimen to Kew, and a figure of it is given in 
Hooker's ‘Icones Plantarum,’ t. 1961, but with very little detail. 
Dr. Henry saw only one tree, and this was in Eastern Szechuen. 
Subsequently Mr. E. H. Wilson, collector for Messrs. James 
Veitch & Sons, discovered about a hundred trees in the same 
region, and succeeded in obtaining a quantity of good seed, from 
which a large stock of plants has been raised. Kew is indebted 
to Messrs. Veitch for the material on which the foregoing 
ooservations were made. 
