262 SOME PHASES OF APPLIED ENTOMOLOGY IN SOUTH AFRICA. 



and domestic animals. In South Africa we are faced with -i 

 great number and variet}^ of insect-borne diseases, many of 

 which are obviously tropical in origin. The development of our 

 civilization in this sub-continent is closely related with the ad- 

 vance' of our knowledge of insects and disease. An eminent 

 American entomologist once remarked to me " that the reclama- 

 tion of Central Africa was a problem which the entomologist 

 must solve." We now know a great deal about medical en- 

 tomology, l)ut we are far from a satisfactory solution of all our 

 troubles, and it is this phase of applied entomology which I 

 consider most important so far as our country is concerned. In 

 conclusion, I shall again quote Professor Hernick : " I have 

 been keenly sensible of the influence of the malarial mosquitoes 

 on the energy, efficiency and accomplishment of a people. And 

 the men now engaged in studying this problem will find them- 

 selves ingratiated into the lives of the people about them, and 

 will add to the prestige of our profession among the people 

 of this country.'' 



(Read, July 6, 1917.) 



Other Universes than Ours. — The possibility 



of spiral nebulae, and particularh- the great nebula in Andromeda, 

 being independent universes, at vast distances from our galaxy, 

 has often been discussed. Strength has been lent to this view 

 by recently published measurements of the proper motion of the 

 Andromeda nebula, according to which there has been no appre- 

 ciable displacement for the last 80 years. It now appears, ac- 

 cording to observations of Slipher and others, that the nebula 

 is approaching our system at the rate of over 700 miles per 

 second. From this it is inferred that the distance of the nebula 

 must 'be immensely great, possibly even greater than that esti- 

 mated by Herschel. Prof. Bohlin's view Avas that this nebula 

 Avas only 19 light years distant from our system. 



