PRESIDENTIAL ADDRESS — SECTION D. 69 



glands of the hosts. Mrs. Adie's work has since been criticised. 

 However, Leishmania morphologically is a herpetomonad and 

 behaves as such. 



The origin of leishmaniasis in man and in dogs has been 

 sought experimentally. Insects, both blood-sucking and non- 

 blood-sucking, are known to harbour many species of Herpe- 

 tomonas, that of the liouse fly, Musca domcstica, known as 

 Hcrpctonionas luuscce doinesiiccc, being the first recorded. Other 

 Diptera, such as species of Sai'cophaga, Lucilia, Stratiomyia, 

 Culex, Melophagus; fleas such as Pulex irvitans, Ctenoceplialus 

 canis and others ; lice and many bugs, both bed bugs and plant 

 bugs, all harbour herpetomonads. The life-histories of many 

 herpetomonads in their insect hosts have been worked out by 

 Patton, Fantham, Porter, Chatton, Laveran and Franchini, 

 among others. The relation of such insect flagellates to verte- 

 brates was elucidated by the independent experimental work of 

 Laveran* and Fi'anchini in France and of Fantham and Porter 

 in England, whose researches in each case have extended over a 

 long jjeriod. The results of these workers may now be 

 summarised. 



Laveran and Franchini, in their early work published in 1913, 

 recorded infections of mice by the inoculation of Hcrpcto})ionas 

 efenoccphaU (from dog-fleas), while they have subsequently 

 obtained similar infections in rats and mice by inoculating or 

 feeding them with H. patloni (from rat-fleas), and in dogs by 

 inoculating them with H. ctenocephali. Crithidia fasciculata from 

 Anoplicles niaculipennis, and Crithidia meJophagia from 

 Mclopliagus ovinus inoculated into white mice and rats have 

 resulted in the infection of the vertebrates with the Crithidia of 

 the insect, the parasite being recovered from their blood and 

 organs. 



Mice were infected with Crithidia fasciculata, and one showed 

 skin lesions on the neck. Dogs and monkeys inoculated from 

 mice infected with the' flea flagellates Hcrpciomonas ctenocephali 

 and H. pattoni have also developed herpetomoniasis. Dogs have 

 also been infected by inoculation of H. phlebotomi and guinea- 

 pigs with H. ctenocephali White mice have been inoculated 

 with H. sarcophagce from Sarcophaga hccmorrhoides, and a 

 recently-described new species of herpetomonad, H. periplanetce, 

 from Blatta orieutalis, has also produced infection in mice. 



An extraordinarily interesting result accrued in 1920, when 

 the French workers succeeded in infecting the plants Euphorhia 

 sauliana and E. pdosa with Hcrpctomonas ctenocephcdi from the 

 dog-flea, inany flagellates occurring in the latex of these plants as 

 a result of the inoculation. 



A converse experiment was also performed, latex of Euphorhia 

 nerciifolia containing a Herpetomonas being injected into white 

 mice and producing infection in the same. 



From the various figures published by Laveran and Franchini. 

 it seems clear that the non-flagellate forms predominated in their 



* See Treatise on " Leishrr.anioses," Paris, 1917. 



