January 20, 19 10] 



NA TURE 



to the east and west ; but thev still retain so much of 

 their primitive folk-lore and beliefs that they deserve special 

 examination. While their legends of the origin of fire and 

 the sun are more or less common to other members of 

 the group, their accounts of the creation and the deluge 

 are peculiar to themselves. In the first, the earth with 

 its great long horns raises itself from the primeval waters. 

 The god Nagaitcho takes his seat upon it, places its head 

 in the direction in which it should lie, and spreads clay 

 between its eyes and upon each horn. Finally, in this he 

 plants trees and other vegetables, and moulds the moun- 

 tains and valleys. 



In a second myth the gods Nagaitcho and Thunder cause 

 the old, worn-out sky to fall, and replace it with a new 

 firmament with four portals and four supporting columns, 

 preparing at the same time summer and winter trails for 

 the sun. Then follows a deluge, and the creation of fish 

 and beasts of the sea. They then make man out of clay 

 and woman out of one of his legs. In another myth 

 Coyote steals the sun, which he finds tied up in a blanket 

 in the house of an old woman. Out of pieces of the sun 

 he creates the moon and stars. This series of myths, with 

 other folk-tales, has been taken down from the lips of 

 Bill Rav, who is apparently the last member of the tribe 

 acquainted wittf the race traditions. Mr. Goddard has 

 published the legends in the native language with an inter- 

 linear translation, and adds a free version which renders 

 them intelligible. He admits that the record is frag- 

 mentary, and that they have probably lost some of their 

 primitive form ; but even with this qualification they will 

 prove of interest to students of comparative mythology. 



T 



SOME APPLICATIOXS OF MICROSCOPY TO 

 MODERN SCIEXCE AND PRACTICAL 

 KNOWLEDGE.' 



HE time is past when a man can expect to make any 

 real contribution to knowledge by spreading his 

 observations over the whole vast range of microscopic 

 objects. In these days, in which the output of research 

 on every subject is enormous, and is increasing rather than 

 diminishing, a man is more likely to make progress and 

 do useful work by taking up a special line and sticking 

 to it. Speaking for those who work -with, rather than at, 

 the microscope, I would advise everyone who wishes his 

 work to be fruitful in results to have a hobby of his own. 

 In making this suggestion, I do not mean that we are all 

 to become narrow specialists, interested in nothing but 

 our own particular subject. Specialisation in work and in 

 research does not necessarily mean specialisation in know- 

 ledge or in interests. The great value of such a club as 

 ours is that by bringing together people occupied in 

 different branches of work it enables one man to know 

 what another man is achieving in a different line, thereby 

 at once widening his outlook and stimulating him in his 

 own work by producing a healthy spirit of emulation. 



My advice, therefore, to the microscopist would be that 

 he should aim at wide knowledge and diffuse interests, 

 but should concentrate his activities and focus his atten- 

 tion on his own particular pet hobby, so that, by master- 

 ing a branch of natural knowledge, he may find himself 

 in a position to advance it. However limited the field of 

 study may be, however insignificant the objects may 

 appear, yet something can always be found which, on the 

 one hand, will illustrate some important and fundamental 

 principle, or, on the other, will prove ultimately to 

 have some direct or indirect bearing on human life and its 

 needs. Let me give two instances in support of this state- 

 ment. To the so-called practical man it may seem a very 

 trivial occupation to worry about such things as 

 Foraminifera, however beautiful their shells may be. Vet 

 these tiny creatures, living in a sphere apparently so remote 

 from our own, furnish wonderful illustrations of the powers 

 and activities of primitive living matter, and Mr. Earland 

 has recently directed our attention to the remarkable 

 property they exhibit of selecting particular materials for 

 building up their houses. This is a most interesting fact, 

 well worthy of further study, especially by experimental 



1 From the presidential address delivered to the O'lekett Mirros'-opical 

 Club on May 7, 1909, by Prof. E. A. Minchin, and published in ihe Journal 

 of the Club for November, 1909. 



KO. 2090, VOL. 82] 



methods, for it indicates that the most primitive and form- 

 less living matter possesses faculties of a kind which we 

 term in higher forms of life instinct or inteUigence. Again, 

 a reputation for being an expert on, let us say, fleas, may 

 provoke a smile from the uninstructed ; but in view of 

 the proved connection between fleas and human disease, 

 especially plague, these paltry insects have now assumed 

 very great importance as objects of study, and we find 

 detailed descriptions of them in the reports of Government 

 commissions. As Lord Crewe remarked in a recent speech, 

 we commonly speak of any very trivial annoyance as a 

 flea-bite ; but we know now that in certain circumstances 

 a flea-bite may cost a man his life. Small wonder, then, 

 that fleas have become important objects of study to man- 

 kind. 



This question of fleas and plague reminds me that I 

 am here, not to preach a sermon, but to give an address, 

 by recalling to my mind the subject which I propose to 

 discuss to-night, namely, some of the remarkable advances 

 that have been made during the last few years in our 

 knowledge of human diseases caused by microscopic para- 

 sites. This is a subject which has now grown to such 

 vast proportions that I must confine myself of necessity 

 to a small part of it, namely, the diseases caused by 

 Protozoa. -As examples, I shall de.al more especially with 

 malaria, sleeping sickness, and yellow fever. 



Malaria is a disease which was well known to the 

 ancients, and is still very rife in many parts of Europe. 

 It appears to have been prevalent formerly in the fen 

 districts of England, but to have died out there from some 

 unexplained reason. It is estimated by Prof. Ronald Ross 

 to cause from a quarter to half the total disease in the 

 tropics. It occurs under at least three forms, known 

 commonlv as tertian, quartan, and pernicious malaria, 

 each of them easily distinguishable clinically, and due to 

 distinct species of the parasite dilTering from one another 

 in morphological characters, but similar in the general 

 features of their life-cycle. 



Until comparatively recent times nothing whatever was 

 known of the nature of malaria or the manner in_ which 

 it was acquired. It was generally believed that it was 

 due to a poisonous miasma which arose from swamps and 

 marshes, a notion conveyed in the name malaria — " bad 

 air." This miasma theory is very prevalent in literature; 

 for instance, in such a work as Dickens's " Martin 

 Chuzzlewit," where the unfortunate settlers in Eden are 

 supposed to contract fever by breathing the exhalations of 

 the swamps. 



The scientific studv of malaria may be dated from 1880, 

 when the parasite was discovered in the blood of fever 

 patients by Laveran, then a military surgeon in .'Mgiers. 

 I.averan examined the blood microscopically, and observed 

 the principal ohas^s of the parasite. It was, however, 

 5ome years before Laveran 's parasite was accepted as the 

 cause of malaria, though it ultimately obtained universal 

 recognition. Even then it remained a mystery how the 

 parasite got into the blood, and many still held to the 

 miasma theory. It was suoposed by some that the parasite 

 passed out of the body and oroduced cvsts or spores which 

 could be disseminated bv the wind, just as the cysts of 

 many Infusoria are known to be carried by aerial currents, 

 and that bv inhaling these air-borne germs the disease was 

 acquired. Others sought for the source of the infection 

 in the contamination of drinking-water. 



It remained for a countrvman of ours to discover the 

 true method of infection. Prof. Ronald Ross, then in the 

 Indian Medical Service, experimented first with the very 

 similar malarial parasites of birds, and found that the 

 infection was taken from one bird to another by mosqui- 

 toes of the genus Culex. Similar experiments on human 

 malaria gave at first negative results, until it was dis- 

 covered that the necessary intermediate host of human 

 malaria was a mosquito belonging to quite a different 

 genus, .'\nopheles. These experiments were confirmed by 

 manv investigators in all parts of the world, and led to 

 results which may be stated in two prooositions, one 

 nositive, one negative, first premising that by a malarial 

 infection is meant a new infection, not a relapse in a 

 person nreviously infected. 



(i) Malaria can be and is conveyed from sick to healthy 

 persons by the agency of mosquitoes. 



