130 Loa papionis n. sp. 
identical (Table VII); on the whole they were most numerous in blood from 
the heart. 
Table VII. 
Distribution of larvae at autopsy—two cases. 
Site 
Blood from auricles and ventricles ... 
Blood from large pulmonary vessels 
Smears from cut surface of lung 
Blood from aorta 
Blood from inferior vena cava 
Blood from superficial vein of forearm 
Smears from cut surface of liver, spleen and kidney 
Larvae 
Numerous 
Present in fair numbers 
99 99 
Scanty 
99 
Very scanty 
Absent 
Questions arising from the absence of diurnal periodicity in 
Papio cynocephalus. 
The liability of man to infection. Apart from cases of sleeping sickness 
and altered sleeping habits, the diurnal periodicity of Ml. loa is so marked that 
human infection with Ml. papionis would seem to be improbable. 
The nature of the intermediate host. The nocturnal periodicity of the larvae 
suggests the transmission of the infection by a night-biting intermediate host. 
1 had started experiments with Anopheles maculipennis, but they were 
interrupted by the war before any conclusions were reached. 
The development of Loa loa and Loa papionis after inoculation by the inter¬ 
mediate host. L. loa is certainly a long-lived parasite, for Manson (1912) quotes 
a case in which the worm was extracted from the eye thirteen years after the 
patient had left Africa. AH observers are agreed that its development must 
be slow, for in villages where nearly all the adults are carriers, larvae are 
absent in the blood of the children, although their chances of infection are 
presumably identical. Yet in spite of these facts, we have no detailed informa¬ 
tion as to the parts of the body inhabited by the parasite before reaching 
sexual maturity. I had no opportunity of examining young baboons, but 
never found immature Loas in the adult animals, although I was able to make 
detailed autopsies under the best conditions. Certainly the female Loas had 
not always been fertilized, but such females were approximately the same size 
as the rest and seemed fully developed in every respect. I shall refer to this 
matter again when considering the subject of immunity. 
The liability of Loa papionis to disease. I can find no reference to diseased 
Loas in the literature, but they are undoubtedly liable to parasitic infections, 
as the following example shows: Three Loas were removed at the autopsy 
of a baboon in which few larvae were found during life. The peculiar dead- 
white appearance of one of them attracting attention, all three were kept for 
further examination. The opaque worm was fully as active as the other two, 
and all three were alive on the following day; nevertheless the opacity was 
due to disease. After fixation and clearing, the cuticle was still very indistinct 
