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the rainy season were infested by adult A. variegatum. The high incidence of A. variegatum infestation and the absence of other common ticks Ti.e. R. s. simus, R. e. evertsi, H. rufipes) on the tiang is of interest. Animals examined immediately after death yielded, besides A. variegatum, only a few H. truncatum and B. decoloratus. In April, two pairs of R. tricuspis and a female of H. leachii muhsami were found on one host and in July four males and seven females of H. aciculifer were removed from an other. The latter species also infested a tiang near Tonj (March).

Also noteworthy is the fact that no ticks were found on a number of WATERBUCKS and WHITE EARED KOBS in the Forest. Three ROAN ANTELOPES were infested by (1) two male and a female H. truncatum and the same number of A. variegatum (September), (2) seven male and a female A. variegatum (August), and (3) a male H. truncatum and a nymphal A. variegatum (March). On a HARTE BEEST shot in July, single adults of A. variegatum and B. decolo ratus were found. An ORIBI obtained In June yielded a male R. tricuspis; another, near Tonj in March, two male R. sulcatus.

MAN

Two pairs of adult R. s. simus and nine nymphal A. variegatum were taken engorging on members of our party in the Forest in February. South of Yirol, a female R. sulcatus was taken while crawling on the collector's leg.

DOMESTIC FOWLS

A. persicus is common at Wau, the only locality in which a search for this tick has been made.

DOMESTIC MAMMALS

HORSES are attacked chiefly by B. decoloratus and R. e. evertsi; several collections from single hosts contain as many as sixty ticks of each species. One horse at Wau was infested by twenty adult A. variegatum, another at Busseri by eleven adults of this tick as well as by three adult R. tricuspis, and others by single males of H. rufipes.

DONKEYS are heavily infested by R. e. evertsi. Found on them in lesser numbers are nymphal A. variegatum, and adults of B. annulatus, B. decoloratus, H. rufipes, and H. truncatum.

A PIG at Wau (August) was infested by five male and two fe male A. variegatum and a pair of adult R. s. simus.

DOGS throughout the Province are almost invariably infested by several specimens of R. s. sanguineus and some serve as host for dozens of nymphs and adults. Rare adults of R. s. simus and H. 1. leachii and nymphs of A. variegatum were also found at various localities. A number of female B. decoloratus from Dinka dogs at Fanjak indicate that where dogs and cattle sleep in the same hut the former are attacked by the latter's para site.

CATS at the Forest and at Wau provided a few specimens of H. leachii muhsami.

3).

CATTLE were observed in all areas shown on the map (Figure

Dinka long-horn cattle are regarded with religious fanaticism by their owners. During the dry season the young tribesmen and their great herds migrate to the toich, low lying pastures along the rivers that are inundated during the floods. At the onset of rain they return to their homeland for grazing. People, dogs, and cattle sleep together around the campfire or in huge, smoke filled huts. It was estimated that a quarter of a million cattle passed the Jur Narrows area, in which the Galual Nyang Forest is situat ed, on their annual trek to the toich, but no estimate of the total livestock population of this Province is available. For twelve months, 1950-1951, the Veterinary Department reported 64,031 hides from Bahr El Ghazal; in contrast, only 775 from Equatoria.

Cattle are almost always parasitized by variable numbers of A. variegatum. The infestations are commonly moderate but not infrequently heavy, as many as fifty to a hundred ticks being found on a single animal. During the dry season the proportion of females to males is in the range of one to five hundred, but late in April it becomes one to fifty, and in July and August

one to twenty. The July-August figures probably represent the peak reproductive season of A. variegatum. A single dry season collection from Wau (February), not included in the breakdown above, was exceptional in that eight females and 35 males were found on a single cow. Nymphs were carefully searched for on many large cattle herds in the Forest area in February but fewer than a dozen were found. This is in notable contrast to the invariable infestation of tiang by nymphs in January and February.

Other species common on cattle in this Province are B. deco. loratus and B. annulatus. In the dry season, B. decoloratus was approximately ten times as common as B. annulatus but during the rains the ratio became more equalized and in some collections B. annulatus exceeded B. decoloratus in numbers. B. decoloratus Is represented in all collections from this Province. Very Light infestations of H. rufipes are frequent but H. truncatum is rep resented by only seven adults in three collections. Exceptional parasites of cattle are A. lepidum (three adults in two collec tions), R. s. simus (six adults in two collections), and a single female R. e. evertsi. This last named tick is so common on sheep, goats, and equines in Bahr El Ghazal that its almost complete ab sence on cattle is striking; it is also common in Equatoria Prov ince collections from cattle.

GOATS and SHEEP are infested chiefly by R. e. evertsi, most collections containing only this species. Other ticks on these animals are A. variegatum and B. decoloratus.

UPPER NILE PROVINCE*

Available data for this poorly explored Province refer chief... ly to localities in the vicinity of Nile steamer wood stations and, Data for this Province are from several lots of specimens in Sudan Government and British Museum (Natural History) collections and small amounts of material obtained by personnel of the Sudan Veterinary Service and by the writer. In this report, some references to Kenisa, on the Upper Nile Bahr El Ghazal border, are included under the latter Province.

to a lesser extent, along the Sobat River and the Malakal_-Juba land track. Host tick relationships in this Province are prob ably similar to those of the east bank of Equatoria Province. Some East African species not yet recorded from the Sudan may occur near the Ethiopian border.

As one travels northwards in this Province the big game animals of Africa gradually decrease in numbers and disappear. Er Renk is the northern boundary of the fine, lean, naked Nilotic tribes of Negro Africa; further on the country is inhabited by white gowned Arabs of unique personal dignity and character.

REPTILIA

Cobras at Kenisa, Nasir, and Er Renk have been found in fested with A. latum while A. exornatum has been collected from monitor lizards at Er Renk.

AVES

R. s. sanguineus and R. s. simus were taken from lesser bustards at Maban.

MAMMALIA

BABOONS are infested by R. s. simus.

GROUND SQUIRRELS at Bor were the source of H. houyi.

A LION at Akobo Post was parasitized by single pairs of R. simus, R. s. sanguineus, and H. 1. leachii and a LEOPARD at Bor by a pair of R. s. simus.

Probable infestation of RHINOCEROS is indicated by King's specimens of A. rhinocerotis from grass near Bor.

WARTHOGS and WILD PIGS shot near Duk Fadiat were hosts of numerous A. variegatum and R. s. simus.

Two BUFFALOS at Rom were infested by six male and four fe male A. lepidum (July).

A ROAN ANTELOPE at Kaka supplied four male A. lepidum and one female R. s. simus. A TORA HARTEBEEST on the Daga Kigille track yielded a few female B. decoloratus.

MAN

Two male R. s. sanguineus feeding on man at Melut were sent for identification.

DOMESTIC FOWLS

Argas persicus has been recovered at Malakal.

DOMESTIC MAMMALS

HORSES, DONKEYS, and MULES are attacked chiefly by R. evertsi but several collections including A. lepidum and B. decoloratus have also been made and others contain R. s. sanguineus and B. annulatus.

A PIG at Maban was infested by two B. decoloratus and three R. e. evertsi.

DOGS at Er Renk and Bor were the source of two unusual tick records, one female Ixodes nairobiensis and one male R. supertritus having been secured by King. The first tick is the only one of this species known from the Sudan and the second, not known from other specimens in this Province, is rare wherever it occurs. Infestation by H. 1. leachii is known only from Sobat; special efforts made to secure this tick at Malakal were unsuccessful. R. s. sanguineus is represented in all collections.

CATTLE density, breeds, and handling habits here are in general similar to those of Bahr El Ghazal and long east-west migrations are undertaken in search of grazing. Herds observed in Upper Nile were invariably parasitized by A. variegatum and B. decoloratus. Frequently included were smaller numbers of A. Iepidum, B. annulatus, H. rufipes, R. e. evertsi, R. s. sanguineus, and R. s. simus. Inclusion of the last two rhipicephalids, not ordinarily found on cattle in the Sudan, is difficult to explain, yet several collections from different localities contain a number

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