MARGAROPUS ANNULATUS 607 



Margaropus annulatus, Say. Male. (Plate LXXVIII, fig. 5.) Second 

 and third segments of palp thinnest in the middle, forming a sharp angle 

 externally. Hypostome with eight rows of teeth. Segments of legs 

 sub-cylindrical ; spurs short ; hooks sub-terminal. Adanal plates free 

 anteriorly, rectangular or sub-triangular in shape ; internal border longer 

 than the external ; posterior border oblique ; accessory plate similar but 

 smaller and usually triangular in shape. Caudal appendage absent. 

 Coxa I has two spurs and an anterior hump or projection visible 

 from the dorsal surface. Length 2'15 to 2'35 mm.; width 1'3 mm. 

 (Neumann) 



Female (fig- 6.) Body as broad in front as behind, slightly con- 

 stricted in the middle. Porose areas large and oval, broader than long. 

 Maximum length 13 mm. ; maximum width 7*5 mm. (Neumann) 



Neumann recognizes the following varieties : australis, calcaratus, 

 decolor at us, caudatus and argentinus. 



Variety australis, Fuller. Hypostome with eight rows of teeth. Male 

 with a well-developed caudal appendage ; adanal plates more chitinous, 

 rectangular and straighter. The female has a shorter scutum and 

 the eyes are nearer the middle of its length ; porose areas short. 

 Length 10 to 11 mm. ; width 6 to 7 mm. (Neumann) This variety 

 is found in Australia, the Philippine Islands, the Antilles, Guatemala, 

 Venezuela, Guiana, Brazil, Argentine Republic, Paraguay and Uruguay. 

 It is parasitic on cattle, horses and dogs. 



Variety calcaratus, Birula. Hypostome with eight rows of teeth. 

 Male without a caudal appendage ; adanal and accessory plates straighter 

 and less chitinous than in the type. Female with scutum shorter 

 and straighter ; eyes nearer the middle of the length of the scutum. 

 Porose areas oval, broader than long. Body relatively straight and long 

 when replete. Calcaratus is found in Algeria, Tunis, Egypt, Abyssinia, 

 Roumania and the Caucasus ; it is parasitic on cattle, horses and 

 sheep. 



Variety decoloratus, Koch, C.L. Male (Plate LXXVIII, fig. 3) with 

 caudal appendage well developed ; adanal and accessory plates pointed 

 on their postero-internal borders. Hypostome with eight, sometimes 

 six, rows of teeth. Female with scutum smaller than in the type ; 

 porose areas also smaller. Hypostome with six, often eight rows of teeth. 

 Decoloratus is found in Cape Colony, Natal, Transvaal, Maurice Island, 

 Demaraland, Benin, Gabon, Cameroon and Togo Land ; it is parasitic on 

 cattle, horses, sheep and goats. 



Variety caudatus, Neumann. Hypostome with eight to ten rows of 



