113 
ON A FILARIA, LOA PAPIONIS N. SP., PARASITIC IN 
PAP 10 CYNOCEPHALUS 1 . 
By C. H. TREADGOLD, M.A., M.D. (Cantab.), D.T.M. (Paris). 
(With Plates VIII and IX.) 
CONTENTS. 
PAGE 
Introduction. 113 
I. Description of adult Loa papionis . . . . . . 114 
II. Description of ova and larvae of Loa papionis .... 120 
III. General Biological Investigations . . . . . . 127 
A. Various parasites observed in Papio cynocephalus . . 127 
B. Eosinophilia in P. cynocephalus .127 
C. A comparison of certain biological phenomena in the 
development of Loa papionis and L. loa . . 128 
A short account of L. loa .128 
The distribution of L. papionis in P. cynocephalus . . 128 
The distribution of Microloa papionis . . . . 129 
Questions arising from the absence of diurnal periodicity in 
P. cynocephalus .130 
The development of L. loa and L. papionis after inoculation 
by the intermediate host.130 
The liability of L. papionis to disease . . . . 130 
The absorption and calcification of dead Loas by the host. 131 
I). The influence of these parasites on their respective hosts . 131 
E. The Treatment of Filarial Disease . . . . . 132 
Summary. .... 133 
References. 133 
INTRODUCTION. 
Before the war, the yellow baboon (Pajpio cynocephalus) was imported in 
considerable numbers by Dr L. C. Query of Paris, who organized the capture 
of these animals by native hunters in the interior of French Guinea and their 
shipment from the port of Conakry. On arrival in Paris, they were utilized 
by him for the production of his antisyphilitic serum. Increasing doses of a 
filtered broth culture of the syphilitic virus were injected subcutaneously, the 
baboons being killed by bleeding from the carotid artery about a month later. 
Having noticed the occasional presence of round worms during the operation 
1 The old name of this species, Cynocephalus babuin, has been condemned for reasons of 
priority. 
8—2 
