316 



GEORGE H. F. NUTTALL. 



2. IXODIDAE. 



The IxoDiDAE comprise nine genera of wnich. all but one (Margaropus) occur in 

 the Belgian Congo. Before considering the differences in these genera "we must 

 dwell briefly upon the structure of an Ixodid tick (see figs. 5 and 6). 







Fig. 5. Ixodes ricinus (Linn.) (^ : ventral and dorsal aspects. In Africa, 

 the species only occurs along the Mediterranean. (Nuttall, 1908). 



JCU/^^^O'ryL 





^onco^ 



^v^cv-a. 





J 





Fig. 6. Ixodes liexagonus, Leach, 1815 ; replete $ : dorsal and ventral aspects. 

 The species does not occur in Africa. (Nuttall, 1911). 



