i88 5 .J 
397 
The Parasites of Civilisation. 
But this consideration meets a part only of the difficulty. 
The question still arises, why, among natural species of 
plants and animals, totally unmodified by man, we find the 
same difference, — the ugly, the useless, and the pernicious 
being more prolific and more tenacious of life than the use* 
ful and the beautiful ? 
We must therefore hazard the suggestion that the attain- 
ment of what strikes us in beauty, whether in form and 
colour, or in sounds emitted and fragrance given off, must in 
reality be an exhaustive strain upon the resources of either 
animal or plant. If this is the case the organic world is 
not developing in the direction of beauty, and the ugly shall 
inherit the earth. 
In concluding we must raise the question, In which of the 
divisions of the animal and vegetable worlds are the para- 
sites upon civilisation mainly to be traced ? Among 
mammals there are few, all rodents, — the mouse, the rat, 
and some allied species. The squirrels are certainly enemies 
of man, as attacking and injuring not a few of his che- 
rished possessions, and destroying harmless and beautiful 
wild birds. But they recede before increasing population, 
and find no shelter in our cities, so that they cannot rank 
among the parasites. One of the worst features of the 
parasitic rodents is that they furnish a pretext, at least, if 
not an adtual necessity, for the cat and the terrier, — two 
most objectionable animals, the dread of all who love flowers 
and birds. 
Among birds we can name only one truly parasitic species 
— the house-sparrow. This bird has not a single redeeming 
feature, and has beyond doubt multiplied, pari' passu, with 
the development and the spread of civilisation. His worst 
feature, next to the unfortunately successful war which 
he wages against the martin and swallow, is that we can 
scarcely extirpate him without scaring away useful and 
harmless birds. 
Of reptiles, amphibia, and fishes, none, from their very 
nature, can rank as parasites upon civilisation. 
The invertebrate parasites space will not allow us to 
discuss in detail. Among mollusks are the terrestrial snails 
and slugs, and among insefts a very considerable number. 
