-163- 



Competence for transmission of L mexicana ssp. has been demonstrated 

 for several New World sand flies, only one of which, Lu. anthophora 

 (Addis), is indigenous to the USA (Kil lick-Kendrick, 1979; Endris, 

 pers. comm. , 1984). 



The specific objectives of this study were to: 



1. investigate, under controlled laboratory conditions, the vector 

 capacity of Lutzomyia diabol ica (Hall), as compared with Lu_. shannoni 

 (Dyar), for leishmaniasis; and 



2. examine by means of the electron microscope the morphology of 

 _L. mexicana parasites found in the sand fly vector. 



Materials and Methods 



Infection of Sand Flies and Parasite Development 



Leishmania mexicana (strain WR-411), isolated in 1980 from a 

 single-lesion infection of an 11-year-old white male from Uvalde, 

 Texas, was the principal pathogen used. It was provided by Walter 

 Reed Army Institute of Research (WRAIR), Washington, D.C., and has 

 been maintained by serial passage in Syrian hamsters for the past 

 three years. Other strains used included L m. amazonensis (strain 

 untyped) provided by Dr. K. P. Chang (Department of Microbiology 

 UHS/Chicago Medical School, North Chicago, Illinois) who obtained it 

 in 1979 from original stock isolated by Dr. P. Marsden from a patient 

 in Tres Bracos, Brazil; L. brazil iensis guyanensis (strain 

 MH0M/SR/80/CUMC 1), provided by Dr. Jan Keithly, Cornell University 

 Medical Center, New York City; and L donovani infantum (untyped) from 

 a naturally infected dog that was presented to the University of 



