302 Bibliographical Notices. 
three of these, viz. highly specialized structures, the absence of 
‘‘infinitely numerous fine transitional forms,” living or extinct, and 
the ‘ polyphyletic hypothesis.” The first of these was fully dealt 
with by Mr. Darwin, who showed for example that even the human 
eye is an imperfect instrument, and that among the lower animals 
we have a very large series of transitional forms of eye, from a mere 
nerve-ending epithelium cell to the eye of a Nautilus, of a lobster, or 
of aman. So, too, we must join issue with Mr. Mivart as to the 
absence of extinct transitional forms. The progress of geology 
even since Mr. Darwin wrote has added enormously to our know- 
ledge of such forms, whilst it has also shown that it is difficult to 
overstate the imperfection of the geological record. In the face of 
such cases as those of the Ammonites described by Wiirtenberger 
and of Planorbis multiformis in the Steinheim Limestone, described 
by Hilgendorf, it is difficult to say that “the mass of palontolo- 
gical evidence is indeed overwhelmingly against minute and gradual 
modification.” Of course these evidences have often, as Hickel 
has shown, been evaded by arguing in a circle as to wide specific 
limits and limited variability; but this only demonstrates the 
meaninglessness of the term “ species.” 
To imagine that the characters of two sets of organisms can so 
have varied as to produce in distant regions the same result is surely 
a greater violence to the ordinary laws of causation than to suppose 
that an organism now found in two such regions has previously 
existed in the area intervening between them. Like causes may 
produce like effects; but in the complexity of organic life and its 
surroundings can causes ever be sufficiently like for this polyphy- 
lesis ? 
Mr. Pascoe’s pamphlet suggests many other topics of interest in 
matters of detail, as, for instance, why man’s action should be ex- 
cepted in discussing the recent extermination of species ; but per- 
haps its chief merit is in the frank statement of difficulties and of 
arguments pro and con without any attempt to set up any agency 
as an alternative to natural selection. ‘A tendency to be wingless ” 
or any other “‘ tendency ” is, it must be remembered, only a state- 
ment, and not even an approach to an explanation. 
G. S. Bounerr. - 
Phytogeogenesis. The Primeval Development of the Crust of the 
Earth and of Plants. Sketched out by Dr. Orro Kunrzz. 
Pp. 213. 8vo. Leipsic: 1884. [Phytogeogenesis. Die vorwelt- 
liche Entwickelung der Erdkruste und der Pflanzen in Grundziigen 
dargestellt von Dr. Orro Kuntze. | 
Tue special objects of consideration in this treatise are the formation 
of the primeval rocks from gasogenous glowing crystals, the gradual 
salinity of the ocean, and the marine development of the coal-plants, 
Having laid down his principles for the reconstruction of primeval 
conditions and his hypothesis on the origin of the first beings, indi- 
