360 BOTANICAL GAZETTE [May 
Thus Cook, in his recognition of the correlation between the 
taxonomic position of the gall-making animal groups and the 
degree of complexity of the galls produced by them respectively, 
has laid, in part, the foundation for the present discussion. In 
Coox’s papers, however, anatomy and etiology are his major con- 
cern. Only in the instance of a few cynipid galls did he present 
the probable phylogenetic relationships. 
Basic data involved in phylogenies 
BEYERINCK (1), in his primary division of galls into those 
characterized by indefinite growth and those exhibiting definite 
growth, made an initial contribution of great significance. KUSTER 
amplified this conception into the following two groups: (1) Kata- 
plasmas; all those galls which are characterized by inconstancy 
and indefiniteness with regard to size and tissue form characters; 
there is also associated an indefinite time element; they invariably 
fall below corresponding normal parts in their differentiation, and 
what differentiation does ensue shows no new fundamental orien- 
tation of tissues as contrasted with the normal arrangement; 
(2) Prosoplasmas; all those galls which are characterized by definite 
size, tissue form, and time of development; in their differentiation 
they are not so much below the normal as they are different from 
the normal; in their form characters and orientation of tissues 
they are fundamentally different from the normal; they may be 
different in other characters as well, such as quality and quantity 
of organic substances contained. 
KUsTER (9, 10) has a preliminary division, his so-called ‘‘ organ- 
oide and histoide” groups. Since the first, consisting of very 
slight modifications of normal organs, can be interpreted as very 
primitive kataplasmas, there is no significance to this classification; 
in the opinion of the writer it may well be discounted. 
Major phylogenetic factors 
1. THE PLANT.—The influence of the plant and its evolution 
are most strikingly observed in the kataplasmas, since these struct- 
ures are for the most part not very far removed in their constitu- 
tion from the condition obtaining in the normal plant. They 
