TRANSACTIONS OF THE SECTIONS. 123 
living, preceded by others which became living before them, and succeeded by new 
ones, ‘hus, during the life of a spherical particle, new centres are continually 
appearing in pre-existing centres. 
3. The oldest particles on the circumference of the spherule, having passed 
through various stages of existence in moving outwards from the centre, gradually 
lose the power of animating lifeless particles, and become resolved into formed 
material, which is destitute of the power of increasing itself, and is no longer 
living. 
4, “The new-formed material is being produced upon the inner surface of that 
already formed—that is, in contact with the germinal matter; so that, passing from 
within outwards, we have (a) germinal matter; (b) imperfectly developed formed 
material; (¢) fully developed formed material. The germinal matter exhibits in 
cases a central portion (nucleus), within which may be one or more portions with 
many circular outline (nacleoli), and within these smaller particles are often to be 
made out (nucleoluli). Passing from within outwards are several zones, the inner- 
most being most intensely coloured by carmine. 
The thickness of the formed material must gradually increase unless the oldest 
part which is outside is removed as fast as new-formed material is produced; in 
the latter case we should have (d) disintegrating formed material. 
The conyersion of inanimate matter into living matter, and the conversion of 
living matter into formed material, are continually taking place during life. The 
formed material, having been produced, is passive. It may be changed or altered, 
but it has no inherent powers of compelling the elements of matter to assume cer- 
tain fixed relations to each other, like the germinal matter. It has ceased to live. 
All the work performed by an organism during its life depends upon the action 
of certain agents upon this formed material. AJl these changes are physical and 
chemical, and can be caused to continue after the organism is dead ; but the formed 
material itself can never be produced artificially, because its composition and pro- 
perties depend upon the particles of germinal matter from which it was produced, 
and these derived their powers from pre-existing living particles, and these from 
their predecessors, and so on, back to the first living particle of that particular 
kind which was created. We can cause the destructive changes to continue after 
death; but the constructive changes cease with life, and cannot be imitated arti- 
ficially. 
The moyements of living particles from centres, and the continual formation of 
new centres within pre-existing centres—the power of inducing similar changes 
in particles otherwise incapable of undergoing change—the progressive modifica- 
tions taking place in a definite order, which end at last in the formation of passive 
substances having properties and chemical composition totally different from those 
of the pabulum on the one hand, and those of the living particles themselves on 
the other,—constitute a series of phenomena which occur in every different kind 
of living matter, and in living matter alone. They cannot be explained in the 
present state of knowledge by physical and chemical actions, and they may still 
be fairly termed zztal phenomena, in contradistinction to those purely physical and. 
chemical changes which occur in the formed material. 
Living matter always possesses the power of inerease and formation, and these 
processes of increase of the living matter, and its conversion into formed material, 
take place respectively under different circumstances. The conditions favourable 
to the increase of the living matter are not favourable to the production of formed 
material. Living matter may inerease very rapidly, but the production of formed 
material is comparatively a slow process. All those tissues which in their perfect 
state are composed of much formed material in proportion to the germinal matter, 
grow slowly. During the earlier periods of their existence their growth was 
more rapid. : 
When a mass of germinal matter becomes surrounded with a thick layer of 
formed material, change, as would be supposed, goes onveryslowly. The pabulum 
passes slowly through the formed material, and in small quantity, so that very 
little germinal matter is produced. The conversion of germinal matter into formed 
material, however, still proceeds until only a very small quantity remains living, 
surrounded on all sides by a thick, passive, and perhaps nearly faparmeabte en- 
