Vegetative Mutations. 621 



to the first generation and bore numerous fruits, ilic sur- 

 face of which was partly thorny and partly sniootli as 

 in D. laevis. Sometimes one-half was smooth, but u;>ually 

 only a quarter or a smaller part. The valves without 

 thorns had also reverted to the character of D. laei'is 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 Ijy 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 Brassiea and Ra- 

 phamis with two types of pods.^ Dounet-Adanson ob- 

 served on an intermediate hybrid between Abies Pinsapo 

 X pectinata a branch with the characters of A. Pitisapor 



FocKE mentions a case of the cross Anagallis pJioe- 

 nicea X coentlea which had red flowers but exhibited 

 half a petal with the blue color of the latter species.*' 

 Vegetative segregations in the fruits of Citrus hybrids 

 have frequently been described."^ Flowers of dilTerent 

 colors have been found occurring together on the same 



^ Sageret, Ann. Sc. Nat., 1826. 



^ Bull. Soc. hot. Fr., 1899; Abbado, Uihridlsmo, lor. cit., p. j6. 



'W. O. FocKE, Nat. Ver. Bremen, 1887. p. 422. Soc als(> Gart- 

 ner, Die Bastavderzeugung,, p. 309, and I'ocke, J'i1iincentni.s-.h!:iiiH', 

 p. 450. 



*Verlot, La variahilite, p. 14; Kerner. Pflancenlehen, IT. pp. 559- 

 560, etc. 



