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also found dividing promastigotes of L chagasi (= L d_. chagasi ) in 

 the thorax as well as in the abdominal midgut of Lu. longipalpis. 



Massive infections of the cardia and stomodeal valve were 

 described by Kil 1 ick-Kendrick (1979), which appear identical to those 

 seen in three-day and older infections of L mexicana in Lu . 

 diabol ica , to include the gel-like matrix that joins masses of 

 promastigotes together. He suggested that this matrix might be of 

 parasitic origin. Its significance remains obscure. 



Ki 1 1 ick-Kendrick (1979) stated that the commonest morphological 

 form in the foregut and hindgut of the sand fly is the 

 "paramastigote", a round or oval parasite with the kinetoplast level 

 with or posterior to the nucleus, and a free flagellum. Although forms 

 that roughly fit this description were seen in L mexicana infections 

 of Lu. diabol ica , they were so far outnumbered by "haptomonads" and 

 "nectomonads" as to be inconspicuous. 



Although parasites were seen on one occasion in the diverticulum, 

 infections in this site are generally assumed to be aberrant and not a 

 normal part of the life cycle (Ki 1 1 ick-Kendrick, 1979). The 

 diverticulum acts as a receptacle for sugar taken by the sand fly and 

 may play a role in osmoregulation, but does not participate directly 

 in digestion of the blood meal. According to Ki 1 1 ick-Kendrick (1979, 

 infections of the diverticulum may arise in two ways: During the act 

 of feeding, infected blood may leak into it, or parasites in the 

 esophagus may be swept into the diverticulum as the fly takes 

 solutions of sugar. 



Other workers have described short-slender, highly active 

 promastigotes with long flagella, the appearance of which coincides 



