In 0. moubata and other argasids, symbiotes may migrate from 

 the malpTghian tubes to the ovaries and developing eggs, thus 

 differing from ixodids in which they directly invade the first 

 sex cells (lludrov 1932). This worker sought the explanation of 

 symbiotic bacteria in the realm of physiologic relations of nu- 

 trition. (See three paragraphs below). 



Argasid symbiotes do not appear to be as pleomorphic as 

 those of ixodids and axe usually of the rod or coccus type though 

 they axe grouped into apparently gelatinous masses or colonies. 

 Rows or chains of granules or filamentous bundles are not seen 

 in these masses. Tick symbiotes have not been artificially cul- 

 tivated although Steinhaus attempted to do so with those from 

 Argas persicus by utilizing flixLds and tiss\ies of the chick 

 embryo"^ /"Steinhaus (1947) 7 



With reference to the "bactericidal action" in the guts of 

 insects and A. persicus and 0. moubata (Duncan 1926), the reader 

 is referred to subsequent findings in the following series of 

 papers on work done with A. persicus ; Anigstein, Whitney, and 

 Micks (1950A,B), Whitney, "Anigstein and Micks (1950), and Micks, 

 Whitney, and Anigstein (1951). The intestinal tract of blood- 

 engorged ticks exhibited significantly higher antibacterial titer 

 than those that had not been fed. Study of animal blood itself 

 revealed erythrocytic enzymatic hydrolysates showing marked in 

 vitro antibacterial effect over a relatively wide spectrum oT" 

 most gram- positive and a few gram-negative organisms. The active 

 principle of the hydrolysate appears to be a peptide amino acid 

 complex, called sanguinin, which, as a powerfxil enzjmiatic inhibitor, 

 represses the growth of several organisms incltjding streptococci, 

 both in vitro amd in vivo . 



The role of sj-mbiotes in producing growth- promoting substances 

 in 0. noubata (and in bedbugs) has been stxilied briefly by De 

 Meillon and Goldberg (1947A,B). Feeding nyraphal and adult ticks 

 on thiamin-deficient rats resulted in almost doubling the time 

 necessary for completing the tampan's life cycle, increasing 

 the interval between blood meals and molting, and an additional 

 molt before reaching maturity. Normal growth and reproduction, 

 however, follow feeding on riboflavin-deficient rats (De Meillon, 

 Thorp, and Hardy 1947). The purpose of these experiments, fol- 



- 178 - 



