46 



NATURE 



[March 20, 19 19 



some learned society where those interested will 

 have the opportunity of making such an examina- 

 tion. J. Reid Moir. 

 One House, Ipswich. 



Protozoal Parasites in Cainozoic Times. 



In the issue of Nature for October 3, 19 18 (p. 95), 

 which has just reached me, is a note on Prof. T. D. A. 

 Cockerell's discovery of two new species of Glossina 

 in the Miocene shales of Colorado. It is said that 

 "Osborn's suggestion that many large Cainozoic 

 m;immals in America may have been destroyed by 

 fly-borne parasites is rendered highly probable by the 

 wider range of tsetse-flies now indicated by Prof. 

 Cockerell." 



I do not see that the conclusion is justified. The 

 co-existence in space and, possibly, time of a species 

 of blood-sucking fly and certain large mammals 



THE PERU-BOLIVIA BOUNDARY 

 COMMISSIONS 

 T^HE search for a scientific frontier has taken 

 -*■ men into many wild and unexplored reg'ions- 

 of the earth's surface, and has, in the ag-gregate^ 

 helped in the accumulation of no mean amount 

 of new geographical knowledge. Those familiar 

 with the true foundations of the map of Africa 

 know well that in many areas the surveys 

 executed by boundary commissions are still the 

 only authorities for geographical positions, and 

 that the boundary surveyor was often the first 

 white man to force his way into hitherto unknown 

 parts. As, further, the surveyor brings with hirti 

 both the equipment and the trained technical skill 

 necessary to garner the very utmost amount of 



Fig. I. — Cojata Pampa, wind-eroded rocks. From " Peru-Bolivia Boundary Commissi- 



affords no grounds for concluding that protozoal para- 

 sites carried by the former destroyed the latter. Do 

 blood-sucking flies in America at the present day 

 destroy wild animals through the medium of the 

 Protozoa they carry? 



I am unaware of any evidence at present that wild 

 animals in Africa are destroyed by the Trypanosomes 

 of which they are the hosts and Glossina the vector ; 

 indeed, there is very definite evidence to the contrary 

 that buck do not suffer in the least from the con- 

 tinued presence in their blood of Trypanosomes which 

 are pathogenic to man and his domestic animals. 



What grounds, then, are there for the assumption 

 that the adaptation of such Protozoa to their hosts 

 was any less perfect in Cainozoic times than at 

 present?' G. D. Hale Carpenter, 



Uganda Medical Service. 



Kome Island, Lake Victoria, January 12. 



NO. 2577, VOL. 103] 



detailed and trustworthy information in the course 

 of his rapid traverse of the country, it follows that, 

 next only to the closely settled districts, the 

 boundary lines in Africa are now the best known 

 regions of the continent. 



The conditions in South America are somewhat 

 similar, but, owing to the fact that most of the 

 international boundaries are almost inaccessible, 

 lying either on the great heights of the Andine 

 Cordillera or hidden in the impenetrable 

 forests of the Upper Amazon and its tribu- 

 taries, the need for actually defining these 

 frontiers on the ground has not generally 



1 "Peru-Bolivia boundary Commission, 1911-13." Reports of the British 

 Officers of the Peruvian Commission. Edited for the Government 

 of Peru by the Royal Geographical Society of London. Pp, xi-f 242-f-maps. 

 (London : Cambridge University Press, 1918.) 



