20 6 W. F. PURCELL, 4 
Aviculariidae, particularly the Trap-door forms, were probably not collected as thoroughly as the other 
spiders, owing to the extreme difficulty generally experienced in discovering their retreats. Nevertheless 
Dr. Schultze obtained at least 7 species, which may with confidence be placed among the trap-door 
building forms, belonging to the genera Idiops, Stasimopus, Pelmatorycler and Ancylotrypa. 
The two largest spiders obtained were a large Harpactira from Great and Little Namaqualand, and 
a new Ceratogyrus from the Kalahari, the latter having a peculiar hörn in the middle of the cephalo- 
thorax above. 
Fam. Aviculariidae. 
Genus Idiops Perty. 
1. Idiops striatipes n. sp. 
1 $ from Sekgoma, Kalahari Desert, Bechuanaland Protectorate, November 1904. 
Colour ochraceous, the abdomen pale-yellowish. Cephalothorax with some radiating infuscated 
marks above, the ocular area also infuscated, the soft skin narrowly blackened all round the edges of the 
cephalothorax. Pedipalps and the two anterior pairs of legs with the tarsi infuscated, reddish-yellow at the 
apex, and provided below with a narrow ochraceous line, those of the pedipalps with a large cuneate yellow 
mark at base above; metatarsi of the two anterior pairs of legs strongly blackened, marked at base above 
like the tarsi of the pedipalps ; tibiae of these legs and of the pedipalps also strongly blackened, the upper 
surface with 2 large yellow bands extending along whole length, the dark band separating them bifid and 
diverging at base, underside paler below in the second pair of legs ; the patellae blackened at the sides in 
the pedipalps and the two anterior pairs of legs ; femora of anterior limbs with some feebly infuscated stripes. 
Abdomen broadly infuscated above anteriorly. 
Cephalothorax (measured along the lateral eyes) as long as the patella, tibia and half the 
metatarsus of first leg, but a little shorter than the tibia and metatarsus of fourth leg. Ocular area 
broader than long, its width about 7 /s of the length of the metatarsus of first leg. Area formed by the 
frontal eyes and the anterior median eyes of the posterior group parallel-sided, its length exceeding its width 
by a diameter of one of its posterior eyes ; the frontal eyes oval, rather large, very close together, the 
common tubercle deeply and angularly grooved above. Posterior lateral eyes long, reniform, their anterior 
margins in a line with the centres of the anterior median eyes, their posterior margins being only just 
anterior to a line touching the hind margins of the posterior median eyes, but distinctly posterior to a line 
joining the centres of these eyes; their distance from the anterior margin of the cephalothorax subequal to 
their distance from the anterior median eye of the other side but less than their distance from the 
corresponding posterior median eye; the four median eyes forming an area which is a little broader behind 
than in front and very much broader than long (but not twice as broad behind as long), the anterior 
medians about an eye's diameter apart, decidedly larger than the small posterior medians, which are sub- 
rotund and distant from each other about one-half further than from the lateral eyes. 
Legs. Tibia of first leg as long as the metatarsus and 2 / 3 of the tarsus. Tibia of second leg with 
a single row of 4 long spines on outer side, the distal spine being slenderer than the other three. Patella 
of third leg with only a pair of short stout spines (overhanging the distal edge of the posterior upper 
surface) in addition to the band on the anterior side, the spiniform setae on the upperside long. All the 
tarsi spined below. 
