CHAPTER III.--NATURE’S REVENGES: THE SLEEPING SICKNESS 159

LIST OF ILLUSTRATIONS

FRONTISPIECE:--Profile views of the Cranial Dome of _Pithecanthropus erectus_, the ape-like man from an ancient river gravel in Java, and of a Greek skull.

FIG. 1.--Frontal view of the Cranial Dome of _Pithecanthropus_ 16

FIG. 2.--Frontal view of the same Greek skull as that shown in the frontispiece 16

FIG. 3.--Eoliths, of ‘borer’ shape, from Ightham, Kent 18

FIG. 4.--Eoliths of trinacrial shape, from Ightham, Kent 20

FIG. 5.--Brain casts of four large Mammals 23

FIG. 6.--_Spironema pallidum_, the microbe of Syphilis discovered by Fritz Schaudinn 37

FIG. 7.--The Canals in Mars 43

FIG. 8.--The Canals in Mars 44

FIG. 9.--Becquerel’s shadow-print obtained by rays from Uranium Salt 73

FIG. 10.--Diagrams of the visible lines of the Spectrum given by incandescent Helium and Radium 76

FIG. 11.--The transformation of Radium Emanation into Helium (spectra) 83

FIG. 12.--Dry-plate photograph of a Nebula and surrounding stars 90

FIG. 13.--The Freshwater Jelly fish, _Limnocodium_ 97

FIG. 14.--Polyp of _Limnocodium_ 97

FIG. 15.--Sense-organ of _Limnocodium_ 97

FIG. 16.--The Freshwater Jelly-fish of Lake Tanganyika 98

FIG. 17.--Sir Harry Johnston’s specimen of the Okapi 99

FIG. 18.--Bandoliers cut from the striped skin of the Okapi 99

FIG. 19.--Skull of the horned male of the Okapi 100

FIG. 20.--The metamorphosis of the young of the common Eel 101

FIG. 21.--A unicellular parasite of the common Octopus, producing spermatozoa 102

FIG. 22.--The _Coccidium_, a microscopic parasite of the Rabbit, producing spermatozoa 102

FIG. 23.--Spermatozoa of a unicellular parasite inhabiting a Centipede 103

FIG. 24.--The motile fertilizing elements (antherozoids or spermatozoa) of a peculiar cone-bearing tree, the _Cycas revoluta_ 104

FIG. 25.--The gigantic extinct Reptile, _Triceratops_ 106

FIG. 26.--A large carnivorous Reptile from the Triassic rocks of North Russia 107

FIG. 27.--The curious fish _Drepanaspis_, from the Old Red Sandstone of Germany 107

FIG. 28.--The oldest Fossil Fish known 108

FIG. 29.--The skull and lower jaw of the ancestral Elephant, _Palæomastodon_, from Egypt 109

FIG. 30.--The latest discovered skull of _Palæomastodon_ 110

FIG. 31.--Skulls of _Meritherium_, an Elephant ancestor, from the Upper Eocene of Egypt 111

FIG. 32.--The nodules on the roots of bean-plants and the nitrogen-fixing microbe, _Bacillus radicola_, which produces them 114

FIG. 33.--The continuity of the protoplasm of vegetable cells 116

FIG. 34.--Diagram of the structures present in a typical organic ‘cell’ 117

FIG. 35.--The Number of the Chromosomes 119

FIG. 36.--The Number of the Chromosomes 120

FIGS. 37 to 42.--Phagocytes engulphing disease germs--drawn by Metschnikoff 136-7

FIG. 43.--A Phagocyte containing three Spirilla, the germs of relapsing fever, which it has engulphed 137

FIG. 44.--The life-history of the Malaria Parasite 142

FIG. 45.--The first blood-cell parasite described, the _Lankesterella_ of Frog’s blood 144

FIG. 46.--Various kinds of Trypanosomes 145

FIG. 47.--The Laboratory of the Marine Biological Association on the Citadel Hill, Plymouth 155

FIG. 48.--The Tsetze fly, _Glossina morsitans_ 172

FIG. 49.--The Trypanosome of Frog’s blood 173

FIG. 50.--The Trypanosome which causes the Sleeping Sickness 176

FIG. 51.--The Trypanosome of the disease called “Dourine” 177

FIGS. 52 to 56.--Stages in the growth and multiplication of a Trypanosome which lives for part of its life in the blood of the little owl, _Athene noctua_, and for the other part in the gut of the common Gnat (_Culex_) 180-3

PREFACE

_This little volume is founded on three discourses which I have slightly modified for the present purpose, and have endeavoured to render interesting by the introduction of illustrative process blocks, which are described sufficiently fully to form a large extension of the original text._

_The first, entitled ‘Nature’s Insurgent Son,’ formed, under another title, the Romanes lecture at Oxford in 1905. Its object is to exhibit in brief the ‘Kingdom of Man,’ to shew that there is undue neglect in the taking over of that possession by mankind, and to urge upon our Universities the duty of acting the leading part in removing that neglect._

_The second is an account, which served as the presidential address to the British Association at York in 1906, of the progress made in the last quarter of a century towards the assumption of his kingship by slowly-moving Man._

_The third, reprinted from the_ Quarterly Review, _is a more detailed account of recent attempts to deal with a terrible disease--the Sleeping Sickness of tropical Africa--and furnishes an example of one of the innumerable directions in which Man brings down disaster on his head by resisting the old rule of selection of the fit and destruction of the unfit, and is painfully forced to the conclusion that knowledge of Nature must be sought and control of her processes eventually obtained. I am glad to be able to state that as a result of the representations of the Tropical Diseases Committee of the Royal Society, and, as I am told, in some measure in consequence of the explanation of the state of things given in this essay, funds have been provided by the Colonial Office for the support of a professorship of Protozoology in the University of London, to which Mr. E. A. Minchin has been appointed. It is recognized that the only way in which we can hope to deal effectually with such diseases as the Sleeping Sickness is by a greatly increased knowledge of the nature and life-history of the parasitic Protozoa which produce those diseases._

_I have to thank Mr. John Murray for permission to reprint the article on Sleeping Sickness, and I am also greatly indebted to scientific colleagues for assistance in the survey of progress given in the second discourse. Amongst these I desire especially to mention Mr. Frederick Soddy, F.R.S., Prof. H. H. Turner, F.R.S., Prof. Sydney Vines, F.R.S., Mr. MacDougal of Oxford, and Prof. Sherrington, F.R.S. To Mr. Perceval Lowell I owe my thanks for permission to copy two of his drawings of Mars, and to the Royal Astronomical Society for the loan of the star-picture on p. 90._

E. RAY LANKESTER, _January, 1907_.

ERRATUM.

Page 98: first line of description beneath Fig. 16., _for_ Limnocodium _read_ Limnocnida.

THE KINGDOM OF MAN