hosts but the full extent of their importance as hosts remains to be studied. Nymphal preferences may differ from those of adults, although in some species this may not be true. Host size appears to be of some importance, for most larvae parasitize small animals; nymphs attack larger animals; and adults feed on the largest available animals, except carnivores. Immature stages, however, more frequently parasitize carnivores. Cattle and, to some extent, other domestic animals are important adult hosts and wild antelopes are also frequently parasitized. The African tortoise, rhinoceros, elephant, and buffalo harbor species mostly restricted to themselves. In general, the domestic animal parasitizing spe cies are well represented in study collections; others are seldom collected. Amblyomma ticks are usually three-host parasites and, so far as known in Africa, there is usually only a single generation an nually. 2. Eyes small, hemispherical, situated in a well defined depression (i.e. orbited)..... Eyes flat or very slightly convex, not in a depression.. 3. Festoons with two colors. (Scutal ornamentation always as illustrated).. Festoons only dark colored... ....3 ..5 .A. LEPIDUM Figures 68 and 69 ..4 4. Scutum with numerous coarse punctations, and with a red lateral spot. (Rare in Sudan).... Scutum smooth, with few scattered coarse 5. Scutum smooth, with only very fine punctations. Eyes slightly convex. (Chiefly from buffalo)... Scutum with scattered large punctations. 6. Smaller than A. marmoreum group, maxi- Size at least 6.0 mm. x 5.0 mm. Dark 7. Scutum dark, ornamented areas small, punctations only small. (Medium size, drab tick, chiefly from elephants)... Scutum extensively ornamented, some .A. POMPOSUM Figures 80 and 81 ..A. VARIEGATUM Figures 92 and 93 ....A. COHAERENS Figures 64 and 65 ...6 ....A. NUTTALLI Figures 76 and 77 ..A. MARMOREUM Figures 72 and 73 .A. THOLLONI Figures 88 and 89 .A. RHINOCEROTIS Figures 84 and 85 FEMALES 1. Eyes in a well-defined depression (i.e. orbited), hemispherical or strongly convex. Eyes not in a depression, flat or 2. Scutal punctations very coarse, uneven, Scutal punctations not so coarse, sur- 3. Scutum narrowly rounded posteriorly; large punctations chiefly in medio lateral area, more or less confluent. Scutum more widely rounded posteriorly, 4. Scutum with central and lateral areas largely pale colored; punctations either large or fine.... Scutum with either central or lateral ..2 ...4 .A. POMPOSUM Figures 82 and 83 .3 ....A. LEPIDUM Figures 70 and 71 ..A. VARIEGATUM Figures 94 and 95 ..5 7 |