502 The Inconstancy of Fasciatcd Races. 



they manifest a certain order in their disposition since 

 they are usually found in that region where other normal 

 and ahnormal characters also attain the maximum of 

 their development.-^ This phenomenon which can easily 

 be demonstrated in the fasciated race of Tetragonia cx- 

 pansa, is, however, in need of more thorough investi- 

 gation. 



But the chief point seems to me to be, as Goebel 

 ]Dointed out in his work to which we have already re- 

 ferred, that the latent factor for the production of anom- 

 alies must be present in all those parts of the plant in 

 which external influences are able to induce fasciations 

 or anomalies. If this is absent no amount of manipula- 

 tion is of any avail. It seems, however, that the factor 

 for the production of fasciations is pretty generally dis- 

 tributed throughout the vegetable kingdom; though it 

 is not so general but that there are certain groups in 

 which it does not occur. It is a curious fact that fascia- 

 tions are much commoner amongst dicotyledons than 

 amongst monocotyledons, although some very well-known 

 instances are ]:)resented by the latter {Asparagus, LUiitin, 

 Fritillaria, Orchis). 



§ 15. HALF RACES WITH HERITABLE FASCIATION. 



It is only by conducting special breeding experiments 

 that we can discover for certain whether fasciation is 

 heritable in a given species, and to what extent. If, 

 however, such cultures are made, we shall soon find that 

 these anomalies fall into two categories which are per- 

 fectly analogous to the half races and eversporting vari- 



^ See T. Tammes, Ucher die Pcriodicit'dt morphohgischer Er- 

 scheinungcn bci den Pflanzcn_ Kon. Acad. v. Wet., Amsterdam. 1903. 



