HANDBUCH DER SYSTEMATISCHEN BOTANIK 61 
which is characterized by Sahar eT flowers with a well- 
iat, corolla than as the stock from which the whole sub- 
class Choripetale, and consequently the whole great class of Dico- 
tyledo ons, has been derived. The author admits a relation between 
d t 
Abies advanced pos pony the dicotyledonous series 
y-. 
The author then traces the evolution of the typical porogamic 
pollen-tube growth in Angiosperms from the primitive meth 
Cycads where the tube is not directly concerned with the transport 
of the male nucleus ; the chalazogamic stage i in Casuarina and ce 
tain inally, 
an attempt is made to derive the eae sect flower from that 
of the Gymnosperms. The simple unisexual flower of the Mono- 
chlamyde@ is assumed to have been pr from an inflorescence— 
thus the whorl of male flowers in Casuarina recalls on the one 
hand the wg of the small flowers in Ephedra, while on 
the other hand it i pppoe os that it has given rise to a simple 
monochlamydeous staminate flower, the bracts becoming the peri- 
anth and the axillary netic mugs flowers. becoming the stamens. 
This looks simple when viewed as a floral diagram, but does the 
sia ee es ocr ms the aide morphological difference 
os e whorl of axillary staminate flowers of Casuarina and 
smple eucyclic flower which he derives — it? The pis- 
tllate flower is derived from a union of a pair of carpels and the 
eo t of the ee flower is raerelaria in such 
inflorescence as occurs, e.g., in # ee where a more 
foie oat is surrounded by m alas flowers 
The greater part of the book is, of course, devoted to the sys- 
tematic ag tine of the series and families, which is on the lines 
familiar to us in the German systems which have grown out of 
that of Eichler. The subject-matter, which is severely systematic, 
ns. The eed = 
development of ‘this eta, through the Aizoacee.  , BR. 
