VULGARIS L. AND IN PH. MULTIFLORUS WILLD. 109 
NEW RESEARCHES. 
a. PHASEOLUS VULGARIS. 
The materials, considered in this paper, came for a part from 
hybrids artificially obtained, partly from Fy-individuals that took 
their origia by spontaneous hybridization. In the first case it was 
very easy to grow the whole Fo-generation ; in the other cases 
also the whole posterity ot an Fy-individual was taken into culti- 
vation. Part of these materials were obtained by the aid of others: 
Messrs C. J. Droogendijk (The Hague), J. D. Koeslag (Wageningen), 
Prof. H. Mayer Gmelin (Wageningen) and N. Raap (Anna Paulow- 
na, N.H.) have supplied me friendly with some hybrids. 
The pure races, that have been used in these hybridizations, 
are: 
1. „Witte” (white) beans with a shining white seedcoat, lacking 
a navelring; 
2. „Citroen” (lemon) beans, lemoncoloured, without or at most 
with a blueish navelring (pl. II, fig. 22); 
3. ,,Wagenaars” have a seedcoat, that immediately after har- 
vesting, is lemon-coloured with a brown navelring, but soon 
the lemoncolour changes into greyish yellow and a year af- 
terwards the seeds are entirely yellowish-brown (pl. Il, fig. 18); 
4, „Bruine” (brown) from the moment of ripening yellowish 
brown on the whole seedcoat and a brown navelring (pl. II, 
PE 
5. „Rotjes”, a race characterised by a grey-brown seedcolour, 
that can be discerned in two types: a dark grey-brown (pl. II, 
fis. 23) and a less intense grey-brown type (pl. II, fig. 24); 
6. „Zwarte” (black) with a pure black seedcoat (pl. II, fig. 16); 
7. „Kievits” (lapwing) with a constant reddish violet marbling 
upon a yellowish groundcoloar as racial character (pl. II, fig. 21). 
Of course in the cultures from artificially obtained hybrids only, 
both parents were known with certainty; a great many spontane- 
ous hybrids however showed in their posterities proportions 
of segregation, that were wholly parallel to those from artificial 
hybrids, and on this ground their descendance gave strong indi- 
