160 



of certain leishmaniform bodies that are insufficiently known, appears 

 a 'priori to find in the bed-bug a host in which it can accomplish its 

 normal development. The geckos examined were taken far away 

 from any human dwelling and in all probability had never been bitten 

 by bugs. It is the more interesting to note that the trypanosomes 

 harboured by them showed themselves capable of developing readily 

 in the intestines of these insects, and much more easily than in 

 artificial media. The surest method of discovering the existence of 

 trypanosomes in a gecko is to have them bitten by bugs and to recover 

 the parasite in the stomach of these insects on the 2nd to 8th day. 

 The trypanosomes undergo no developmental change in the intestine 

 of the bug. The culture appears to reach its maximum towards the 

 5th or 6th day and obviously degenerates when the digestion of blood 

 is complete. The develoj)ment of the trypanosome of the gecko in 

 the bug is a simple temporary culture in the blood AAnthdrawn from the 

 gecko, which constitutes a favourable medium so long as it is not 

 completely digested. The role of the bug is merely to prevent the 

 putrefaction of the blood by means of its intestinal secretions. This 

 fact illustrates the power possessed by certain trypanosomes of 

 developing in some animal quite distinct from their normal 

 intermediate host, and the impossibility of ascribing with certainty 

 the role of natural vector to the insect that lends itself to such 

 development. 



An infection by Trypanosoma cruzi lasting 5 months was obtained 

 by Brumpt in 1912 in the bed-bug with transformation of the 

 trypanosomes into crithidial bodies and a return to small trypanosomes 

 capable of causing infection ; this was a case, not of a simple culture, 

 but of true development. 



These observations indicate that the favourable host is not 

 necessarily the natural host, nor even an allied species, and may 

 be an animal that cannot be described as a host in the parasitic 

 sense of the word.§ 



Leger (M.). Contribution a I'Etude de la Faune culicidienne de la 

 Guyane francaise. [Contribution to the Study of the Culicid 

 Fauna of French Guiana.] — Bull. Soc. Path. Exot., Paris, xi, no. 5, 

 8th May 1918, pp. 397-400. 



Mosquito-borne diseases are of such importance in French Guiana 

 that they have seriously impeded repeated attempts at colonisation, 

 periodical outbreaks of malaria, filariasis and yellow fever having 

 retarded the development of the colony throughout the 19th century. 

 The species of Anophelines and Culicines found in the colony are 

 reviewed, with the type of locality in which they are found. Only 

 two Anophelines are known to occur, namely, Anopheles {Cellia) 

 argyrotarsis, Desv., and A. (C.) albimanus, Wied. {cubensis, Agr., 

 albipes, Theo.), the latter being the more abundant species. 



Culicines identified by the author include : Culex fatigans, Wied., 

 C. digiiutus, Rond., C. mathisi, Nev.-Lem., C. favipes, Macq., Aedes 

 {Culicelsa) taeniorhynchus, Wied., Taeniorhynchus fasciohtus, Arri., 

 T. (Mansonia) amazonensis, Theo., Melanoconion atratum, Theo., 

 Stegomyia fasciata, F., and S. Inciensis, Theo., a variety of the 

 last-named. 



