THE VITAL AND PHYSICAL FORCES. 
733 
II. The multipUcation of the cell, by spontaneous division or fission, is a process 
intimately connected with its growth, and takes place under precisely the same 
influences. It is by this kind of multiplication, that the simpler forms of vegetation 
are chiefly extended ; and that the “germinal mass” is produced in the higher, the 
component ceils of which, resembling each other in all their ostensible characters, 
seem to be nothing else than repetitions of that in which they all originated. 
III. But from this homogeneous germinal mass, a complex and heterogeneous 
fabric is gradually evolved, of which the several parts or organs present wide diver- 
sities in structure and endowments. In this process of evolution or development 
(which obviously differs essentially both from growth and multiplication) it is usual 
to regard two separate agencies as in operation ; namely. Morphological Transfor- 
mation, which is concerned in the evolution of the several organs of which the entire 
body is composed ; and Histological Transformation , the operation of which is limited 
to the component tissues of which these several organs are made up. It appears to 
the author, however, that, strictly speaking, there is but one such force ; the form 
as well as the composition of each organ being determined by the development of 
particular tissues, and by their multiplication in one direction rather than another ; he 
would therefore consider that the transformation of the simple primordial cells into 
other forms of tissue is the only indication of a distinct force which is manifested in 
the development of the fabric. Its assumption of its complete and perfect structure, 
is the result of that perfect harmony and balancing of the several forces of growth, 
multipUcation, and transformation, which indicates, in the most distinct and unmis- 
takeable manner, the controlling and sustaining action of an intelligent mind, acting 
in accordance with a determinate plan*. 
In the life of the fully-developed organism, we have still to trace the persistence of 
the same phenomena; for this is entirely made up of the vital manifestations of its 
component parts ; and these, in the plant, are either cells of various forms, or are 
tubes formed by the coalescence of cells, which minister simply to the conveyance 
of liquids. The vegetable physiologist has long been familiar with the fact, that all 
the operations of the most truly vital nature are performed in cells, which have not 
departed in any considerable degree from their primitive type. These operations do 
not essentially differ in the most elaborate vegetable structure, from those which are 
performed in the simplest plants, and in the earliest stage of development of the more 
complex ; the chief difference being, that the products of the actions of individual cells 
* The term “germ-force’' has been employed by Mr., Paget (Lectures on Repair and Reproduction) to de- 
signate the power which each germ possesses “ to develope itself into the perfection of an appropriate specific 
form.” The author has elsewhere shown (Brit, and For. Med.-Chir. Review, Oct. 1849, p 413) that this 
term cannot be logically understood as anything else than “ a comprehensive expression of all the individual 
forces which are separately concerned in the evolution, maintenance, and reparation of a living being.” And so 
far from regarding the whole force which produces the evolution as being possessed by, or as residing in, the 
germ, it will be the author’s object to prove that it is of external origin. 
