Evolution / by Patrick Geddes and J. Arthur Thomson.

  • Patrick Geddes
Date:
[1911?]
Catalogue details

Licence: Public Domain Mark

Credit: Evolution / by Patrick Geddes and J. Arthur Thomson. Source: Wellcome Collection.

    108/264 (page 104)
    gruesome lists of pestiferous creatures and lurking dangers, of that dream of this as the best of all possible worlds to which a too facile evolutionism has been wont to incline. Species of all manner of groups, he shows us, may fall into parasitism, the simplest bacteria and lower fungi, the more active and long supposed innocent Protozoa above all— so that for a generation past the vast field of pathology has seemed well-nigh divided between bacteriologist and parasitologist proper. It is among the Vertebrates, which only fall into parasitism in the rarest cases, that infestation is most frequent. Fishes may even swarm externally with trematodes and parasitic crustaceans, internally with cysts and intestinal worms without number. A vivid impression of the prevalence of parasitism is afforded by the capture, not infrequent at a channel zoological station or by fisher folk anywhere, of the huge and majestic sunfish, Orthagoriscus mola; and by picking off with forceps into museum bottles his crowds of uninvited passengers—the tuft of barnacles upon his back, the biting isopods like enormous fleas upon his skin, the trema¬ todes sucking like leeches upon his eyes; and within to find not only his alimentary canal crammed with worms more than with food,