eee we ee TRES T 
28 PKOF. JULIUS MACLEOD ON TEN 
Table XXX. (breadth of the border): the minimum table excludes 
rostratum, perhaps affine (and also subglobosum, spinosum, and punctatum 
previously excluded), 
Eight species are already excluded. The stem æ is thus probaby cuspi- 
datum, perhaps affine. 
Table XXIX. (number of cells) does not give an answer. 
Table XXVIII. (breadth of the cells): here the minimum table is decisive, 
affine is excluded. 
The stem æ belongs thus to the species Mn. cuspidatum : the first identi- 
fication is confirmed (continued $ 19). 
$18. THE QUANTITATIVE DESCRIPTION OF ONE INDIVIDUAL (BERTIL- 
LONAGE): its value for descriptive botany and zoology.—The description of one 
individual of Mnium cuspidatum given in § 17* may be compared with the 
well-known bertillonage, which is the quantitative description of a person. 
A bertillonage is a combination of figures obtained by the measurement 
of a certain number of characters of a person n. As a given combination 
practically never occurs a second time, it is characteristic of the person n ; it 
enables us to differentiate n from any other human individual whatever, and 
thus to identify it. 
In a similar way the quantitative description of an animal or a vegetable 
specimen enables us:—1°, to discover the species to which it belongs (by 
means of maximum and minimum tables) ; 2°, to differentiate it from any 
other living individual of the same species or of any species whatever. 
Ithinkit would be very useful to add to the description of a new species 
the quantitative description of a few or at least of one specimen T. By 
means of the exact information given in such a description we would be 
enabled to identify later on the described species, even if the type is 
lost. 
In innumerable cases it is possible to make a sufficient number of measure- 
ments without disturbing the specimens. I succeeded in measuring 38 
characters of thousands of specimens of Carabus mounted on needles (more 
than 250,000 measurements) practically without spoiling them, except in the 
early days when I had not yet had enough practice in the work i. In 
the case of the Mosses and other minute objects (small insects, Crustacea, 
flowers, etc.) one is compelled to dissect the specimens, but in case of need 
* To this description the gradation curves of the characters a-/ might have been added, 
but this was useless for our purpose. 
T Measuring as many characters as possible. 
f If one wants to measure precious specimens (specimens of certain species of Carabus 
have a value of 10 shillings each and even more) it is advisable to practise at first by 
measuring similar, but valueless objects. 
