1898] CURRENT LITERATURE 2g1 
development; young forms. Sectéon IV. Malformations and their signifi- 
cance for organography: how malformations arise, significance of malforma- 
tions for the theory of formation of organs. Section V. Influence of corre- 
lations and external stimuli upon form. 
These topics are treated in a clear and concise manner, in German which 
itisa pleasure to read. If any parts be selected as instructive above others, 
they would be, in our judgment, the fourth and fifth sections, in which the 
uthor discusses the relation of teratology to organography and the formative 
influence of external stimuli. 
In the former, after pointing out the impossibility of an exact definition of 
amormalities as distinguished from variations, he shows that monstrosities 
uenot lawless, since the fundament (Az/age) of a shoot is never misdevel- 
ped into a leaf or root, nor a sporangial fundament into a vegetative organ. 
For when stamens or carpels are malformed, it is always the nut 
Which are developed, while the sporangia are dwarfed. Such structures 
Mt reversionary in the least, but are due to pathological disturbances, 
‘amot lead to any correct phylogenetic conclusions. Malformations in gen- 
tral, Goebel holds, are either inherited (of which he cites numerous exam- 
amples), their development at any particular time, however, being often 
wupled with the action of external conditions, in whose absence they persist 
‘latent fundaments; or the: external factors are the causal impetus of mal- 
formations, especially in the lower plants, though examples among sees 
. are hot wanting. The study of monstrosities leads to the conclusion 
that Sachs’ theory of “Stoff und Form”’ is the most satisfactory one, ?. he 
_. in the forms of organs are due to differences in the plastic 
and 
in discussing correlations the author points out two general categories: 
%€, which he 
— pe form of organs such as thorns, sporophylls, 
eects of 5 discussing the influence of external stimu 
Moitine woul, light, medium, and mechanical stimuli are ©) 
i... ould convey an idea. | _ 
: teed 1s. attempt to get out of a rut, the very effort Is likely to carry © 
. i. ee of the road. To this we must ascribe Goebel’s pees 
| te dea . term “leaf fundament”’ (Blattanlage) on the ground 3 
ae taf” is a mere abstraction, there can be no such thing as 4 
: sth only fundaments of foliage leaves, scale leaves, ete: In sup- 
OR angles position he argues that if the theory of meaner 
been led ‘a the examination of roots instead of leaves, It would not hav 
“othing Such vagaries, or have generalized the concept 
“emained but an abstraction. Botanists would have more 
ted, of whic 
clearly 
