144 
The Scottish Naturalist. 
rare occurrence, but it is so, and any effort to remove the barrier which has 
hitherto existed between Biology and Palaeontology is, in our opinion, worthy 
all praise. From this point of view, the work is a most useful one, and we 
congratulate the authors upon the outcome of their labours. 
The work is at once recognised as an expansion of the numerous contribu- 
tions (especially the admirable article on " Mammalia ") to the Encyclopcedia 
Britannica by the senior author. 
Chapter I. deals with a general definition of the Mammalia, the limits and 
connections of the class and the economic uses to which they have been put. 
Following this is a necessarily somewhat lengthy chapter of 74 pages, in 
which the general anatomical characters are considered. Efere the section on 
the Dental-system may be mentioned as specially good, but its usefulness 
would doubtless have been enhanced by the introduction of more numerous 
illustrations had the space permitted it. Chapter III. is devoted to 
the origin and classification of Mammals. In discussing the phylogamy 
of the group, the most recent evidence is taken into account, but the con- 
clusions arrived at still tend to support the view long ago advanced by 
Professor Huxley, that the immediate progenitors of Mammals must be sought 
for, not among the Samopsida, but as low down as Amphibia. The notes on 
classification wind up with a concise table of the Orders, Sub-orders and 
Families — the extinct forms being at once distinguished from the living by a 
conspicuous difference in type. Geographical and Geological Distribution 
constitute the next section of the work. From Chapter V. onwards the differ- 
ent Orders and Families are taken in succession, beginning with the Mono- 
tretnes and ending with the Hominidcp. In this last section the Human 
Family is dealt with, and we find much information of general interest bearing 
upon the characters and origin of the different races of Mankind — a subject 
upon which Professor Flower speaks with special authority as an anthropo- 
logist of eminence. It is quite unnecessary to deal with the chapters on the 
different groups individually, for there is little if anything to criticise, unless it 
be that we cannot help feeling that in some cases the descriptions of the fossil 
forms are briefer than we should have wished, for there is no doubt that a 
very considerable proportion of those who consult the work will come in 
search of information on the palaeontological side. The illustrations arc 
mostly excellent,, the majority of which will be familiar to many as having 
previously done service in the Encyclopcedia Britannica articles referred to. 
