668 The Philippine Journal of Science 
The guinea pig whose liver was heavily infested thirteen days 
after feeding eggs failed to show larve in the lungs, kidneys, 
spleen, pancreas, blood vessels, and spinal fluid. 
SUMMARY 
The observations recorded in this paper may be summarized 
as follows: ; 
1. Eggs of Ascaris vitolorum were observed to develop rapidly 
under the influence of tropical conditions, and many contained 
embryos in about. ten to twelve days. 
2. Ingestion of embryonated eggs by experimental animals 
resulted in the hatching of the embryos in the intestine and 
the elimination of undeveloped eggs and of dead embryonated 
eggs with the dejecta from the alimentary canal. 
3. Hatching is apparently the result of the activities of the 
larve under the stimulus of body temperature and probably 
also of the general intestinal environment. 
4, The eggs of Ascaris vitolorum can withstand drying if 
they are protected from the direct rays of the sun. Dry and 
moist eggs are rapidly destroyed by tropical sunlight, the 
destructive action being independent of the light rays. The 
temperature under which these experiments were carried out 
was 45° C., 
5. The larve of Ascaris vitolorum were found to linger in 
the liver of guinea pigs for longer periods than the larve of 
A. lumbricoides and were still present in the liver after the lungs 
had become free from parasites. This appears to indicate 
an arrest of larve in that organ. 
6. In heavy experimental infections other organs besides the 
lungs and liver, notably the kidneys, were heavily invaded by 
larve. 
7. Guinea pigs appear to be more resistant to the effects of 
the invasion of the lungs by larve of A. vitoloruwm than they are 
to the effects of a similar invasion by larvee of A. lumbricoides. 
REFERENCES 
1. FULLEBORN, F. Untersuchungen liber den Infektionsweg bei Strongy- 
loides und Ankylostomum und die Biologie dieser Parasiten. Beiheft 
(5) Arch. f. Schiffs- u. Tropen-Hyg., Path. u. Therap. exot. Krankh., 
Leipzig 24 (1914) 340. 
2. RANSom, B. H., and Cram, E. B. The course of migration of Ascaris 
‘larvae. Am. Journ. Trop. Med. 24 (1921) 129, 
3. ScHwartz, BENJAMIN. Ascarid infestations of domestic animals in the 
Philippine Islands. Philip. Agri. Rev. ( 1922). In press, 
4. YosHipa, Sapao. On the migrating course of ascarid larve in the body 
of the host. Journ. Parasitol. 6 (1919) 19. 
