610 
IVE CLR LE: 
[APRIL 29, 1897 
researches of Masterman, which, if confirmed, must 
result in the placing of P/oronts among those peculiar 
allies of the early ancestors of the vertebrates known as 
Hemichordata. Perhaps it will be possible to introduce 
Ninny 
i mint f 
Fic. 2.—A schematic view of the interior of the body of Phoronis, with the 
middle 2 omitted. Magnification, which is great, is not stated. 
it again in a subsequent volume for the convenience of 
comparative study. With regard to Phoronis kow- 
alevskii, Mr. Shipley tells us that it is a name “ given by 
= 
Fic. 3.—A. Stickleback (Gastevosteus) infested by an advanced larva of 
Schistocephalus. B. The larva. Both x ra. 
Benham to the species from Naples described by Cald- 
well, and replaces the name /4. c@sfztosa, which was 
given, but subsequently withdrawn, by Cori.” This 
seems a roundabout way of stating that Coris name was, 
NO. 1435, VOL. 55 | 
as he has admitted, antedated by the name given by 
Benham. A name, once published, cannot be “with- 
drawn,” even by its author 
The volume concludes with an excellent index ; but a 
review of any volume of the “ Cambridge Natural History” 
that should conclude without an allusion to the admirable 
illustrations would indeed be incomplete. In this re- 
spect the present volume, though dealing with less pic- 
turesque animals, by no means falls short of its prede- 
cessors. As clear presentations of anatomical structure, 
we may draw attention to a diagram of Plavaria on p. 
39, of Leptoplana on p. 14, of Phoronis’ on p. 457, of 
Alcyonidium on p. 469, and many like them. 
We may also notice the figures drawn from specimens 
in the Cambridge Museum, such as the stickleback # in- 
fested with a cestode larva, on p. 84, and many taken 
from the most modern writers, other than the authors, as 
Biirger, Haswell, Spencer, and others. Indeed, the only 
complaint we have to make with regard to the figures is 
that the name of the artist does not appear to be given 
in the volume. 
Taken as a whole, the book is fully worthy of its place 
in this attractive series, and, even if the eye of a critical 
zoologist may detect a shortcoming here and there, his 
heart must be gladdened to see a general work published 
at last that treats these generally despised animals in a 
style to which their morphological importance entitles 
them. 
INDIA-RUBBER AND GUTTA-PERCHA, AND 
THEIR SOURCES. 
HE question of the supply of india-rubber to meet 
the present enormous demands caused by the 
progress of electrical science, and the rapid develop- 
ment of the application of the substance for cycle and 
carriage tyres, is one that has been much discussed of 
late, and continues to increase in interest. For some 
time past it has been well known that the trees which 
supply the best rubber known in commerce, namely, Para 
rubber, have been more and more difficult to get at, in 
consequence of the collectors having to proceed further 
into the forests in search of the trees (Hevea brasiliensis) 
which yield the valuable juice. But though greater 
distances have to be traversed in order to collect the 
rubber, there seems but little fear of the absolute failure 
of the rubber supply generally, or cf this one particular 
kind. Though the quality of this rubber is of a very 
superior nature, we are fortunately not dependent alone 
upon it for the supplies of our markets, for from the East 
and West Coasts, as well as from Central Africa, and also 
from India and the Far East, we obtain very respectable 
quantities ; indeed, the resources from tropical Africa in 
this respect have of late so much increased, that they 
promise to compensate for any loss of the American sup- 
plies, and the experiences of the past year or so, when a 
new source of rubber has been discovered at Lagos, is 
even more reassuring as to the future supplies, for other 
plants may yet be found capable of assisting in furnishing 
a substance that will probably, in the future, be in still 
greater demand than it is even now. So that it has 
become necessary for every one interested in this 
peculiar industry to take every precaution to prevent 
waste of material, both in the processes of collecting the 
milky juices and in the preservation of the plants yielding 
them. 
It seems pretty certain that, whatever takes place in 
the discovery of new sources, the plants yielding these 
elastic juices must belong to one of three natural 
orders, for all the known plants furnishing rubber of 
commerce belong to the Euphorbiacex, the Urticaceiw, 
1 Reproduced here by permission of the publishers. 
