150 Proceedings of the Eoyal Society of Edinburgh. [Sess.. 
merely simple cells, occupying the borderland between the animal and 
vegetable kingdoms. From the cellular starting-point the development of 
mankind may be traced through a series of intermediate forms, gradually 
rising in complexity of structure with a corresponding specialisation of 
function, without the intervention of special acts of creation — as held by the 
earlier geologists. And here it is of importance to emphasise the fact that 
these intermediate links, or fossil ancestors, were all more or less different 
from each other, the later ones coming nearer to the existing types of 
mankind. The modifications thus effected were chiefly due to climatal 
alterations, the struggle for the ever-fluctuating means of subsistence, and 
some obscure variations in embryonic development, the result being the 
evolution of successors with more highly differentiated organs. On the 
other hand, concurrent with the natural causes which improved the species- 
there are others which have an opposite effect. The process of degenera- 
tion which takes place in course of the life-history of certain animals is 
thus graphically described by Sir E. Ray Lankester : “ Any new set of 
conditions coming to an animal which render its food and safety very 
easily obtained, seems to lead, as a rule, to degeneration : just as an active, 
healthy man sometimes degenerates when he becomes suddenly possessed 
of a fortune ; or as Rome degenerated when possessed of the riches of the 
ancient world. The habit of parasitism clearly acts on animal organisa- 
tion in this way. Let the parasitic life once be secured, and away go legs, 
jaws, eyes, and ears. The active, highly-gifted crab, insect, or annelid 
may become a mere sac, absorbing nourishment and laying eggs ” 
(Degeneration, p. 33). 
Among the more specialised of the lower animals the killing of one or 
more of their own species excites some alarm and fear, but little or no sense 
of compassion for the victims, nor do they manifest towards each other any 
altruistic attentions in cases of injury or sickness, except such as take their 
origin in duties emanating from parentage in the breeding season. Sudden 
cataclysms in the material world take place regardless of consequences to 
animal life. The death of thousands of innocent lives from the effects of 
earthquakes, volcanic eruptions, shipwrecks, explosions, abnormal floodings, 
etc., is of frequent occurrence, with as little manifestation of remorse as 
that of a man-eating tiger in the act of devouring his victim. The destruc- 
tion of life due to the working of natural laws, the torturing of a mouse by 
a cat to make the poor timid beast a more palatable morsel, and the 
cruelties inflicted on helpless non-combatants in time of war, may be 
regarded as parallel acts, so far as the working of the laws of nature is 
concerned. The question of morality as regards physical suffering is. 
