374 Leishmania, Herpetomonas, and Crithidia 
suffering from visceral leishmaniasis in the Mediterranean region. I have 
carried out experiments the results of which I will briefly relate. Fleas in¬ 
fected with parasites which I defined as of “leishmanial type,” taken from 
dogs and children infected with leishmaniasis, were put upon healthy dogs. 
These parasites produced in healthy dogs an infection with the characteristic 
symptomatology of leishmaniasis; and characteristic leishmanial forms were 
found in the haematopoietic organs. Similar parasites in fleas were inoculated 
intraperitoneally into white mice and produced in these animals an infection 
which has been determined by microscopical examination of the internal 
organs to be identical with leishmaniasis of infantile or canine origin. 
My investigations have been confirmed by Sergent, Lheritier and Lemaire 
(1912). 
While I, and subsequently Sergent and his collaborators, have made use 
of fleas taken from children and dogs infected with leishmaniasis, Sangiorgi 
(1911) began a series of experimental control investigations with a Herpeto- 
monas in Ctenoceplialus serraticeps, of unknown origin; unfortunately, the 
dogs of which he made use died a few days after the beginning of the experi¬ 
ment and before Sangiorgi was able to arrive at any conclusion. 
A. Porter for a long period of time allowed fleas (Pulex irritans ) infected 
with parasites of the Herpetomonas-tjpe to suck blood from her arm every 
day, but she did not note any infection in herself. Noeller, also, obtained 
negative results from the intraperitoneal inoculation of dogs with the in¬ 
testinal contents of Ctenocephalus serraticeps infected with Herpetomonas 
ctenocephali ; Negri obtained similar negative results from puppies (not pub¬ 
lished), and Chatton from white mice ( Mus albinus). 
To these negative results we can oppose a series of positive results. 
Laveran and Franchini obtained in young rats an infection of the internal 
organs with parasites of a “leishmanial type,” by inoculation, by natural 
means (puncture of the skin and by the digestive tract), making use of dog- 
fleas naturally infected with Herpetomonas ctenocephali. They obtained similar 
results also with rat-fleas (Ceratophyllus fasciatus) infected with Herpetomonas 
pattoni, with Melophagus ovinus infected with Crithidia melophagia and with 
Anopheles infected with Crithidia fasciculata, with Sarcophaga hemorroidalis , 
Phlebotomus, and Blatta orientalis infected with protozoa of herpetomonad 
and crithidial types, and finally by injecting cultures of Herpetomonas cteno¬ 
cephali and of Crithidia melophagia. 
The same writers prepared an emulsion in physiological saline solution of 
the internal organs of those rats experimentally infected with herpetomoniasis 
and injected it into dogs and monkeys, in which animals they obtained the 
reproduction of an infection not distinguishable from that which is observed 
after inoculation with Leishmania. 
Fantham and Porter have experimentally demonstrated that Insectan 
Flagellates, such as Herpetomonas jaculum (Leger), of Nepa cinerea, Herpeto¬ 
monas ctenocephali (Fantham), Herpetomonas stratiomyae, Herpetomonas pedi- 
