1872] 3 
OUR BOOK SHELF 
leontographica. Beitriige zur Naturgeschichte der 
Vorwelt, herausgegeben von Dr. W. Dunker and Dr. 
. A. Zittel. Band XX. Lief. 5. September 1872. 
ndon : Williams and Norgate.) . 
S part of the “ Palzeontographica” contains a continu- 
ation of Dr. Geinitz’s description of the fossils of the 
Lower Quader Sandstone of the Valley of the Elbe in 
ixony, and includes an account of the Brachiopoda and 
he early families (Hippuritidee, Ostracidze, Spondylide, 
and Pectinidz) of the Pelecypoda. The species are care- 
fully described and beautifully figured, and the synonymy 
and distribution of them are discussed at some length, so 
| that the work must be regarded as indispensable for the 
‘student of the Cretaceous rocks. 
_ In some general remarks prefixed to his descriptions 
Dr. Geinitz calls attention to the interest attaching to these 
‘Saxon fossils, in some cases owing to their wide geogra- 
hical range, in others to their long range in time during 
e Cretaceous period. Thus of the species here noticed, 
Ostrea carinata, diluviana,andhippopodium, Exogyra late- 
‘alts, columba, and haliotoidea, Pecten membranaceus, and 
curvatus, Vola phaseola, guinguecostata,and guadricostata, 
and Zima tecta, are common to the Cretaceous rocks of 
' the Elbe Valley in Saxony and of Southern India, in both 
which localities the lower members of the Cretaceous 
series (Neocomian and Gault) are wanting. Juoceramus 
labiatus and Ammonites peramplus are also referred to as 
fossils common to the two localities. On the other hand 
a collection of Cretaceous fossils from the neighbourhood 
of Colorado city and the north of New Mexico also in- 
cluded examples of Znoceramus labiatus, Ammonites per- 
amplus, Baculites baculoides, Inoceramus Brongniarti, 
and a species resembling J/. striatus, evidently represent- 
‘ing the Middle Planer of the Elbe Valley, and derived 
from similar beds of Chalk-marl, over which lie beds with 
Inoc. Goldfussianus, Baculites,and Scaphites, evidently be- 
longing to the age of the White Chalk. These facts, as 
Dr. Gcinitz remarks, furnish support to the assumption of 
migrations of species from India to Europe, or from 
_ Europe to America, long before the human race took the 
same road. 
__ The most interesting cases of the long-continued ex- 
istence of species are those relating to the occurrence 
_ thus low down in the Cretaceous series of species common 
_ to these deposits and to the latest beds of this formation in 
_ the province of Schonen in Sweden. Dr. Geinitz also 
_ calls attention to the variations occurring in the species 
here noticed, and to the apparent interdependence of many 
of those in older and newer parts of the formation, so 
that, as he says, “it is not difficult to sketch a regular 
genealogical tree for various series.” 
Theoretische Maschinenlehre. Von Dr. F. Grashof. In 
_ vier Banden. Erster Band. Erste Lieferung. (Lon- 
_ don: Williams and Norgate.) 
THE first number of this work has been issued during the 
‘present year. From the preface we learn that the object 
of the work is the theoretical investigation of the pro- 
_ blems involved in the theory of machinery. In the first 
volume will be discussed the mechanical theory of heat, 
the theory of hydraulics, and certain other parts of theo- 
_ retical physics and of applied mechanics, which will be 
useful in the subsequent portions. The second volume 
will contain the elements of machines, of mechanical 
-movements, and of governors, and also of mechanical 
_ instruments—z.c., instruments for measuring time, velocity, 
_ mass, force, and energy. 
_. The third volume discusses the machines which serve 
_ for the application of natural agents to technical purposes, 
- machines for employing the power of animals, hydraulic 
_ wheels, windmills, steam engines, and especially heat 
- engines in the widest sense. Finally, the fourth volume 
45 
maschinen)—that is, machines for moving about and 
hoisting solid, liquid, and gaseous bodies (locomotives, 
screw-propellers, winding machines, rams, pumps, blow- 
ing machines), also machines for the working and ma- 
nipulation of rigid bodies, such as hammering and rolling 
machines, sawing machines, &c. 
The number which lies before us principally discusses 
the mechanical theory of heat. This subject is entered 
into with great thoroughness and profundity, and includes 
an elaborate discussion upon radiant heat and many other 
collateral matters. It need hardly be added that for the 
perusal of this work a sound knowledge of mathematics 
is indispensable. 
LETTERS TO THE EDITOR 
[The Editor does not hold himself responsible for opinions expressed 
by his correspondents. No notice is taken of anonymous 
communications. ] 
Kew Gardens and the National Herbarium 
Pror. OWEN has very imperfectly stated the facts respecting 
the cultivation of the ipecacuanha plant at Kew and in India. 
My friend Mr. McNab says of the ipecacuanha (Trans. Bot. 
Soc., vol. x. 319): ‘It is a plant of remarkably slow growth ; 
the largest plant in the Botanic Garden at Edinburgh is scarcely 
one foot in height, although more than thirty years of age, and 
has three leading shoots, each four inches in length. The method 
hitherto adopted of propagating the Cephaélis (as far as I am 
aware) is by cuttings, but of these not more than one or two can 
be got at a time, and at long intervals.” : 
It was the possession in the Edinburgh Botanic Garden of old 
long-established plants, with well-developed, rhizome-like root- 
lets, and the difficulty experienced there in obtaining cuttings, 
which suggested to Mr. McNab a method of propagation. which 
has since been found exceedingly successful, and for which he 
deserves every possible credit. In a printed report to the Secre- 
tary of State for India (11695) Dr. Anderson states: “ It was 
when examining the old plants in order that the best method of 
propagating might be determined on, that it occurred to Mr, 
McNab that the numerous root-Jike tubers might be taken advan- 
tage of as a means of rapidly increasing the plant.” 
At Kew no such great difficulty has been experienced in in- 
creasing the ipecacuanha by ordinary cuttings, the original speci- 
men having during the last six years been by this means increased 
manifold. On the other hand, the constant demand for cuttings 
from the Kew plant has prevented the formation of the tuberous 
rhizomes which in the case of the Edinburgh one were the result 
of thirty years’ growth. 
As far as the resources of Kew Gardens would allow, all 
three presidencies of India were supplied with ipecacuanha plants, 
not once only, but at various times. Most of these perished in 
India, some from being planted in unsuitable sites, others from 
accident ; and it was not till 1868 that its cultivation promised 
success, upon which its propagation on an extensive scale was 
ordered by the Government of India. 
Of the plants sent to Calcutta from Kew, one which arrived in 
1866 had in 1869 produced twenty plants (Anderson, I.c. p. 3) ; of 
these twelve were sent to Sikkim, where seven were ‘‘ killed by a 
coolie falling on them and completely smashing them” (Report 
of the Calcutta Botanic Garden, April 25, 1871). The further 
history of the remainder is detailed in Dr. King’s report, which ~ 
is quoted by Prof. Owen, but in a very unfair manner. The 
passage which he has extracted proceeds as follows beyond the 
point where he stops: ‘‘The five plants in Sikkim were, early 
in the current year, submitted by Messrs. Gammie, Bierman, and 
Jaffrey, of the Cinchona plantations, to a most successful experi- 
ment in artificial propagation, by which four hundred cuttings 
were obtained, the greater proportion of which have formed good 
_ will be occupied with machines for doing work (Avde‘t- | roots, and are now fine healthy little plants.” | 
wierd Sl ateen TCl 14 tik ah ete. 2 
: id ee | 
va 
