C. Basile 
375 
culi, and Crithidia gerridis, if inoculated intraperitonea]ly, or if ingested, can 
live and multiply in the blood and in the internal organs of young rats and 
of dogs and produce in these animals an infection indistinguishable from 
visceral leishmaniasis. 
In later experiments Fantham and Porter have also demonstrated that a 
similar herpetomoniasis can be produced also in cold-blooded animals; they 
have, in fact, produced an infection with Herpetomonas jaculum and Crithidia 
gerridis , both by natural means (the digestive tract) and by experimental 
means (inoculation) in fishes (Gasterosteus aculeatus), frogs, toads, lizards 
(Lacerta vivipara) and in snakes (Tropidonotus natrix ), parasites being present 
in the internal organs indistinguishable from those met with in leishmaniasis. 
But in addition to these experiments the investigations of natural herpeto- 
moniases in animals are highly interesting. 
Dutton and Todd in 1903 observed the natural occurrence of a Herpeto- 
monas in the blood of a rat in Gambia; Fantham and Porter in 1909 again 
discovered this Herpetomonas in the blood of rats inoculated with spirochae- 
tosis. 
Sergent, Lheritier aijd Lemaire in prosecuting their researches in Biskra 
on Tarentola mauritanica established that, in making cultures of the internal 
organs of Tarentola on blood agar, in 15-7 per cent, of the cases forms of 
Herpetomonas morphologically indistinguishable from the cultural forms of 
Leishmania were obtained; on this discovery they based the hypothesis that 
Tarentola mauritanica may be a “reservoir 5 host of Leishmania tropica. 
Leger has recently affirmed that 2 per cent, of the saurians of the species 
Anolis show a blood infection of Leptomonas {Leptomonas henrici) which he 
believes to be of intestinal origin because the same Leptomonas was found in 
50 per cent, of the individuals examined. 
These facts now known to science show that in mammals, as in fishes, 
reptiles and amphibia (especially in those which are insectivorous) natural 
herpetomoniases exist, or an infection with an insectan Herpetomonas may be 
induced, either by way of the digestive tract or by inoculation. Herpetomoni¬ 
asis appears to be an infection which until to-day has not been distinguishable, 
either by the morphological and biological characteristics of the parasite or 
by its symptoms, from visceral leishmaniasis. 
In my previous work on this subject I have already expressed my belief 
that the leishmaniases are produced by Protozoa {Herpetomonas and perhaps 
also Crithidia) which have adapted themselves to live and multiply in verte¬ 
brate hosts; this adaptation is easier in the case of the vertebrate on which the 
insects are ectoparasitic. 
The same species of Herpetomonas of insects, under different conditions, 
may not have any pathogenic action, or may produce pathogenic effects in 
various degrees in different animal hosts. Referring especially to Mediter¬ 
ranean leishmaniasis this theory explains the acute forms, the chronic forms 
and the other spontaneously curable forms which have been distinguished in 
