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MOREL, P. (1956 correspondence). French West Africa. On Centropus

senegalensis at Gorom (50 km. from Dakar), Mbour (100 km. from
Dakar on Atlantic coast), and Barmako (French Sudan). On
Francolinus bicalcaratus at Barmako and Bouake (Ivory Coast).
On Ptilostomis ater at Gorom. All stages of this tick on
these birds.


MOREL, P. (1956 correspondence). French West Africa. On Euxerus

erythropus at Nioro, French Sudan (adults and nymphs), and at
Massakori, Tchad, about forty kilometers east of Lake Tchad


TENDEIRO (1955). Mozambique. Review of previous reports from



TENDEIRO (1935). Mozambique. Review of previous reports from

colony (as H. leachii indica).



USSR. As H. detritum rubrum: description. ?As H. volgense and H. uralense: notes (see page 407). As if. verae: description (see page 407).


transmission of theilerosis in zebu cattle.


USSR. H. detritum, ability of males to transmit theilerosis, in spite of the slight amount of blood they imbibe, to zebu cattle after having fed on infected hosts in immature stages.


KURCHATOV & KAIMYKOV (1934). USSR. As H. volgense:

tion (see page 407).

DEMIDOVA (1942). USSR, Uzbekistan. As H. volgense:

As H. volgense: gives an
account of methods of grazing and quartering cattle in
Uzbekistan and importance of knowing where ticks seek
shelter around buildings and farmyards due to their im
portance in transmission of human and animal diseases.
A few engorged females found in cracks in walls 10 to
15 cm. above ground. See also H. excavatum, page

BARBETTI (1943). Yugoslavia. H. scupense, presence in southern

Croatia. No other Hyalomma species listed. GALUZO & LIVOVA (1945). USSR. H. detritum

For review of other reports on this tick by Galuzo, see

page 411.

An ecological study in the Gissarian Valley to determine the fate of engorged females that drop from cattle in various situa tions and the effect of environmental factors on time of hatching, this field study merits careful attention. Although cattle wander over a variety of biotopes, H. detritum is encountered in only certain of these. In the field it is difficult to discover more than an occasional engorged female on the ground, even when pas. tures are dug up, manure is scattered, and grass is pulled out by the roots. Earlier studies, aimed at determining whether fem males detach from the host during the day while cattle are in the field or at night when they are confined, had shown that en gorged females fall to the ground at any time of the day or night. Females might be expected to find suitable niches for hiding, prooviposition resting, and egg laying in grass roots, rodent burrows, reptile haunts, "insect nests", cracks and crevices in the soil, or under cakes of cow dung, lumps of earth, stones, grass bedding, or the like. Observations preliminary to the present experiment showed that when the temperature is particularly high (from 35oc. to 40°c.) and the sunlight extremely strong, females leaving the host immediately crawl into any shaded place and, if possible, burrow into the soil or hide in cracks or crevices. Females that depart their host in the eve ning crawl slowly over the soil until they find a crack or cre vice. This they enter as deeply as the size of their body will permit. They may pass one apparently suitable niche or enter it

and depart again in search of another. Rodent burrows, grass roots, or spaces under cow dung or stones are not chosen in preference to cracks in soil or under grass bedding. Oviposition commences from ten to fourteen days after leaving the host.

To observe the effect of the environment of niches in various biotopes on oviposition and the life cycle, engorged females were placed in each conceivable type of situation (in test tubes 10 cm. long, 2 to 3 cm. in diameter; into one end four reeds 10 cm. in length were placed and cheesecloth wrapped around them, the oppo site end plugged with cotton; cheesecloth end placed down).

l. Northern slopes of hills, without roots, i.e. ploughed or overgrazed, no wild or cultivated vegetation; where untouched a variety of vegetation persists (scientific names given). Two tubes containing engorged females were placed in cracks in soil, two in "insect nests," one in a rodent burrow, four under grass roots, and two under a cake or cow dung.

2. Southern slopes of hills, which are considerably steeper than northern slopes and covered by a thinner layer of loess but with more vegetation near the summit; little cultivated or not at all; annual grasses with many xerophilic perennials; almost no cracks in soil, rodent burrows, or "insect nests. Here the only place in which a female may hide is in shallow interstices of an nual grass roots; three tubes were placed in this situation.

The remainder of the experiment was undertaken in an irrigated part of the valley, a weakly undulating plain of river deposits and mostly under cultivation.

3. Mountain steppe (in lower part of valley); neglected weed patches of different age. The only hiding places for ticks are in cracks in soil and under grass bedding; four tubes placed in each of these situations.

4. Irrigated, cultivated plots, rice, melons, etc.; pre viously used melon field now deserted and overgrown by weeds utilized for experiment; five tubes placed in cracks of soil, two tubes under roots of grass. Owing to frequent irrigation, these were the only situations in which ticks could survive.

5. Banks of irrigation ditches; these are numerous and covered by grasses and other plants; three tubes placed under bedding of dead vegetation among roots.

6. Cattle sleeping places on north slopes of hills; lacking vegetation, soil cracks, or stones, but with cattle dung mixed with loess dust; only place for females is powdered mixture of loess and cow dung; three tubes placed here and one under an entire cake of cow dung.

Results: in tubes in cracks in soil in any situation lar. vae hatched most quickly (37 to 50 days). Among grass roots in irrigated valleys and meadow steppes, larvae hatched in 68 or 69 days. Females in all other situations perished without ovipositing.

The microclimate of these niches was determined as follows:

[blocks in formation]

Temperature was ascertained by means of a mercury thermometer or, in deeper niches, by a Strelmikov thermocouple. Humidity was determined by Burton's dew point device. Observations were made twice a month every two hours of the day from 24 July to 6 September.

On northern hill slopes, air temperature in soil cracks fluctuated from 22°c. to 28o6. in one day but in a Meriones burrow on the same slope only from 23.5°c. to 26.0°C. In the morning, RH was maximum (54%), at 1300 minimim (40%). In these places, hatching was most rapid.

In tubes on the soil surface among herbage, on southern hill slopes, in which females died, air temperature before sunrise was 19.0°c. but at midday 45.3°C. RH varied from 27% at 1100 to 60% at 2300,

In certain soil cracks where RH fell to extreme midday lows, (10 or 15%), eggs perished.

Tubes among grass roots in mountain steppes and in irrigated plots, in which larvae hatched more slowly than in those in soil cracks, experienced daily temperatures ranging from 13.5°c. to 29.0°c. in the former biotope and from 14.5°c. to 31.5°C. in the latter. RH in the former varied from 34% to 100%, in the latter from 32% to 95%. A number of other data are provided, but these are the high points and indicate the overall planning, methods, and results of the experiment. [Translated copies of the entire paper may be obtained from NAMRU-3, Cairo. The translation con tains certain irregularities that may slightly modify some of the above statements but the general approach is of interest.) SCHULZE (1950B). France.

France. As H. steineri enigki anum subsp. nov.: includes description and illustration of male with mis

formed capitulum. ABRAMOV, TSAPRUN & LEBEDEV (1950). USSR. H. detritum, importance

as transmitter of equine piroplasmosis. PERVOMAISKY (1954). USSP.. H. scupense, morphological variation.

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