Vegetative Mutations. 621 
to the first generation and bore numerous fruits, the sur- 
face of which was partly thorny and partly smooth as 
in D. laevis. Sometimes one-half was smooth, but usually 
only a quarter or a smaller part. The valves without 
thorns had also reverted to the character of D. laevis in 
the fact that they were shorter than the thorned ones, 
and so did not fit into them properly. Fertilization had 
been left to insects, so that the results obtained by sowing 
the seeds would have been of no value. Such vegetative 
segregations appear, however, to be very rare in Datura. 
Other investigators do not seem to have obtained them; 
and I have myself frequently made extensive cultures of 
this hybrid in the hope of obtaining some, but as yet 
without success. 
The records of instances of hybrid segregation are 
scattered through the literature of this subject, so that 
it may be worth while to give the following selection. 
SAGERET obtained a hybrid between Brassica and Ra- 
/ 
phamis with two types of pods. 1 DOUNET-ADANSON ob- 
served on an intermediate hybrid between Abies Pinsapo 
X pectinata a branch with the characters of A. Pinsapo. 2 
FOCKE mentions a case of the cross Anagallis phoe- 
nicea X coerulea which had red flowers but exhibited 
half a petal with the blue color of the latter species. 3 
Vegetative segregations in the fruits of Citrus hybrids 
have frequently been described. 4 Flowers of different 
colors have been found occurring together on the same 
1 SAGERET, Ann. Sc. Nat., 1826. 
2 Bull. Soc. hot. Fr., 1899; ABBADO, L'ibridismo, loc. cit., p. 26. 
3 W. O. FOCKE, Nat. Ver. Bremen, 1887, p. 422. See also GART- 
NER, Die Bastarderzeugung, p. 309, and FOCKE, Pflansenmischlinge, 
p. 450. 
4 VERLOT, La variabilite, p. 14; KERNER, PAanzcnkben, II, pp. 559- 
560, etc. 
