Bibliographical Notice. 59 
who in other classes of plants, and in the animal kingdom, shall in due 
time follow in the track so ably marked out by Mr. Watson, and thus 
at length give us a complete system of the distribution of the exist- 
ing fauna and flora of Britain. Not that it is desirable to attempt 
rash generalizations upon the range of any species within Great 
Britain ; but we think an English naturalist will have done his duty, 
and have done it well, when he has arranged, in a manner so ready 
for reference, as many valuable details as those given in the ‘ Cybele 
Britannica.’ : 
A first step has already been taken towards tracing the range of 
some of our Insects (Butterflies and Sphingina) through the same 
eighteen districts as the Flowering Plants ; and we hope the system 
of the ‘Cybele’ will soon become generally adopted by English 
Faunists. Too much care cannot be exercised in strictly conforming 
to the rules laid down by Mr. Watson ; and, as was said before, the 
mention of the authorities in each case will be a most desirable addi- 
tion. It is hardly to be hoped that a similar exactness or fulness 
of detail is to be obtained at once in the’various classes; but if even 
the horizontal range be carefully traced, it will be a great gain to the 
philosophic naturalist. We could wish, for instance, that the accom- 
plished author of the ‘British Quadrupeds’ would, in his second 
edition, devote two or three pages to a sketch of Mammal distribu- 
tion, as this would afford an opportunity of comparing more strictly 
the respective range of the so-called “faunas” and “floras” of 
Edward Forbes, in part founded upon the “‘types”’ of Mr. Watson. 
On this subject our author remarks (pp. § and 506 of vol. iv.) that, 
although prepared to admit the possible soundness of Forbes’s idea 
of a difference in age between the alpine and lowland floras, he does 
not see the necessity of granting that there is any real distinctness 
between the other ‘‘types.”’ The plants are collected into groups 
only because they present a close resemblance in the direction of 
their increase and decrease; and if this be suggestive of a migration, 
it by no means equally indicates a difference of age and origin be- 
tween the groups. It is often so difficult to assign a plant to any 
one type, that Mr. Watson has been compelled to have recourse to a 
double system of letters to indicate the species whose distribution is 
of this intermediate or uncertain character. Moreover, considerable 
changes have been made, since the appearance of the earlier volumes, 
by removing species from one “type”? to another. Thus the “ At- 
lantic”’ has 9 added, and 18 removed, chiefly to the “ English” type. 
The proportions and constituents of the “ Germanic” are still more 
altered, no less than 43 species being added, and about 30 taken 
away. ‘The totals at present remain—127 for the “Germanic” 
against 69 for the ‘‘ Atlantic,” which thus becomes hardly more 
than one-half as large as the former, instead of about equal, as esti- 
mated in 1847. Mr. Watson also urges that the “types” are, after 
all, little more than “‘ elimatal arrangements,” determined by actual 
physical conditions: besides, it is well observed that it is easy to 
divide into as many groups the flora of any country, yet the geolo- 
gical history of each is utterly different. Such are some of the 
