CELATYCHEUS,—SELENOPS. 115 
much smaller, their diameter equal to one-third of that of the central posteriors, scarcely half a diameter 
apart. Lateral anteriors very minute, oblique, their anterior margin forming with that of the central 
posteriors a recurved line. Clypeus equal to the diameter of an anterior central eye. Tibise i. and ii. 
with 2—2—2—2—2 spines beneath, the apical pair smaller (the male has two lateral ones on the outside 
—one dorso-apical, and one on the inner side towards the base). Protarsi i. and ii, with 2—2—2 spines 
beneath. Scopula absent. Tarsi with claw-tufts and two claws. Lower margin of fang-groove with 
five equal teeth. 
1, Celetycheus paradoxus, sp.n. (Tab. VIII. figg. 13, 13a, ¢.) 
Type, ¢, in coll. Godman & Salvin. Total length 8 millim. 
d. The colours of the single specimen have faded. Its identification will be best determined by the structure 
of the palpal organs; while its general characters will be found under the generic diagnosis, 
Hab. Panama, Bugaba (Champion). 
Fam. SELENOPIDA. 
Legs laterigrade. Carapace and abdomen very much compressed. Eyes more or less in one transverse row, 
much compressed together longitudinally, Other characters generally similar to those of the Clubionidex. 
The spiders belonging to this family form a group very distinct and easily 
recognizable. That they were originally Clubionide there is little doubt, but, under 
pressure of circumstances, they have become flattened out and the legs have been 
forced to assume a. laterigrade position. They live under stones and the bark of trees, 
squeezing themselves into the narrowest crevices. The ability to squat quite flat into 
a depression in the stone under which they are concealed, or on the surface when on 
the look-out for prey, gives them many advantages in the struggle for life. It is 
interesting to note the effect of this environmental compression on the eyes. The 
lateral posteriors remain more or less in the normal position, merely advancing forward. 
The central posteriors, however, have been pressed forward till, in some cases, they are 
almost in a line with and outside of the central anteriors; in other cases (S. minutus, 
F, P.-Cambr.) they are not advanced so far forward. This same forcing forward of the 
central posteriors has pressed the lateral anteriors further apart, and the compression 
of the carapace has reduced the longitudinal ocular area and the height of the clypeus 
to a minimum. 
SELENOPS. 
Selenops, Latreille, Nouv. Dict. d’Hist. Nat. xxx. p. 579 (1819), 
Type S. radiatus, Latr. Spain. 
There is no doubt that the name Selenops was selected by Dufour, but adopted and 
published by Latreille the year before Dufour’s work appeared. _ Latreille characterized 
the genus, and selected as the type a species discovered in Spain by Dufour which he 
named S. radiatus. Dufour called this species, a year later, S. homalosoma. It is 
quite possible that the name Hypoplatewa, MacLeay, will have to be revived for a 
Qf 2 
