172 

 (191) of Infloresfiences, caused by Kall-lnsftr»f«? nr^ri o-on «io.r,<-o « 



«Si/!^?''J' ""^^J^ i^ ''*^'^°'' *° ^^1* ^^«n ''l^^^ considering 

 ™? f^iJ-^yperplasias we will find -no common ohnracterlstics.. 



?^ «f 1 *^L2 Fo*^?Ji«>n of heteroplastic tissue is involved 

 eSn^Ji;: i?*i? ^® either extraordinarily simple histologicallv. 

 showing little or no differentiation. Xnd as a result the ' 



S?;"^L°^4^?°*!^ii*^®^ ^^ ^^^ ^'i*^ i» "arrested developments"- 

 ?L!?®°HJ^ differentiations which bring about structures en- 

 TJireiy different from those known in normal tissues. Vfs will 

 call tissue formations of the first kind kataplasmatic galls 

 or kataplasmr.s, and galls of the second kind prosoplasmatic 

 ^v f °I prosoplasmas, v/e will base the division of our 

 QDundant material upon the given differences between the for- 

 mer and the latter* Even with the help of this principle of 

 division we will not be able to set up two entirelv distinct 



§!!°^?®i^^^*^I^^*^ ^*^ "^^® ^'® ^'il^ only rarely be uncertain as 

 to Whether the separate gall forms belong to this or that 

 group. One could perhaps add to those galls, conceived as 

 transitional between kataplasmes and prosoplasmas, the others, 

 which, in spiteof their very simgle tissue structure, develop 

 "new" characteristics - in that the cells show abundant anth- 

 , ooyanin content, instead of being colorless or containing 

 chlorophyll, or cells occur in them abnormally rich in cyto- 

 plasm, starch content etc. We will observe here that "typical" 

 and unnuestionable prosoplasmas often contain other cell-forms 

 than those of the corresponding tissue of normal plants end 

 that further the different kinds cf elements participating in 

 their Construction are united' into well-defined zones. 



It is to the Interest Of a natural classification to con- 

 sider the morphological character ist i eg of galls together with 

 their histology. We will show that' galls with kataplasmatic 

 tissue characteristics hage no definite outer forms and no def- 

 inite size, Heteroplasmatio galls show varying sizes and forms 

 just as do callus tissued, formations of wound-wood and the 

 fields of Erineum galls. We find, however, where galls of 

 proBoplasmntic tissue structures ar© involved, that the outer 

 appearance of the galls assumes "new" characters, being char- 

 acterized by definite proportions of size and form. Kata- 

 plasmas are 6ften produced by the action of parasitic fungi, 

 which in the inner part of the host plant take up a field of 

 distribution of varying extent, or after infection by animals 

 which live freely on the apper surface of the diseased organ 

 and by their wandering can indefinitely enlarge the field of 

 their stimulation. Prosoplasmas are produced by the action of 

 domiciled organisms, the extent of the field of stimulation re- 

 maining the same under all oircximstances. Further, the differ- 

 ent effective periods of the stimuli, which produce the galls, 

 must be considered. The stimulus caused by producers of proso- 

 plasmas is felt only in definite phases of their development, 

 which, in various species"!^ is enacted in a certain number of 

 (192) weeks and months, while any constant period of stimulatory 



action seems absent in kataplasraas the producers of Which can 

 often grow to be many years old and still be effective. We , 

 will be able to explain the histological differences between 

 kataplasmas and prosoplasmas only by the specific quality of 

 the effective gall-stimuli. But we \7ill venture to trace the 

 constancy, or rather the variability of the f«>|3n and size pro- 

 portions in different galli-products to the temporal and local 

 extent of the effect of the stimulus. 



