330 NATURAL SCIENCE. May, 
THE PEOPLING OF THE WORLD. 
Tue last of those valuable ‘‘ Erganzungshefte’’ (number 107), 
published at intervals by the proprietors of Peteymann’s Mitteilungen, is 
devoted to the ‘‘ Peopling of the World.” Drs. Hermann Wagner 
and Alexander Supan have to be thanked for the prodigious labour 
involved in the compilation of this great census, the mass of figures 
in which is simply appalling. The number consists of 130 pp., and 
is crammed with information. The continents are taken in order, 
and, whenever possible, the census of the actual town is given in 
1891. Details of the previous census are also given in each case, so 
that the reader may see at a glance the increase of population ina 
certain number of years. Towards the end comes a list of the large 
cities of the world and their inhabitants, and we extract the first six 
as having special interest :— 
London (1891) ee aie bic Is Be fs 4,415,958 
Paris (1891) ve ot oe Se at 2,712,598 
New York and Brooklyn (1890) .. us - ee 2,352,150 
Berlin (1890) ae a oe fA on fe 1,763,543 
Canton (1891) 36 ae 20 36 56 ae 1,600,000 
Vienna (1890) aA y- a6 Ae ss an 1,364,548 
There are only 12 cities with over a million inhabitants, of which 
China rejoices in possessing four. 
FRESH-WATER MEDUS#. 
SPECIMENS Of the fresh-water Medusa from Lake Tanganyika, the 
same probably as that referred to by Béhm in 1883, and Wissmann 
in 1887, have been received in good condition, and form the subject 
of a paper by Mr. R. T. Giinther in the April number of the Aznals 
and Magazine of Nat. Hist. The individuals vary in size from 1 to 
1*8c. across the bell, while the largest measured as much as 2°2c. 
The umbrella is flattened; the tentacles very numerous, varying in 
length, and arranged to a sixth order with great regularity. Mr. 
Ginther establishes a new genus, Limnocnida, for this interesting 
animal, and preserves Béhm’s name of tanganjice for the species, 
that author having recognised the form as new, although he was 
unable to describe it in 1883 for want of the necessary literature. 
The fresh-water Medusa which thrives in certain years in the tank at 
the Botanic Gardens, Regent’s Park, Limnocodium sowerbiui, differs con- 
siderably from this new form. 
THE PLAGUE OF VOLES. 
WE have referred on several occasions to the subject of the 
plague of Field-Voles in Scotland, and we shall, therefore, merely 
chronicle the publication of the ‘‘ Report of the Departmental Com- 
mittee on Field-Voles (Scotland), Parl. Paper—C.—6943, 1893, price 
