1896.] SPIDERS FROM THE LOWER AMAZONS. 757 
than half a diameter from anterior laterals. Anterior laterals 
ellipsoidal, their axes one-half longer than diameter of anterior 
centrals. Posterior centrals smallest, oval, less than their trans- 
verse diameter from anterior centrals, only one-half the transverse 
diameter from posterior laterals. Posterior laterals ellipsoidal, 
their axes almost equal to diameter of anterior centrals; less than 
half their transverse diameter from anterior laterals. Anterior 
row procurved. 
Mandibles parallel-sided ; fang-groove armed on inner side with 
a series of 12 stout conical teeth; floor studded with a single 
distinct row of 12 small cusps, diminishing in size towards the 
base, where are also numerous irregular small cusps. Outer 
margin fringed with thickly-set rufous hairs, four at the base being 
stouter and separate. 
Sternum a little longer than broad, smooth, set with black sepa- 
rate hairs; sigilla distinct, submarginal. Zabiwn broader than 
long, convex, smooth, not studded with cusps; set with long black 
bristles. Coxa of pedipalp twice as long as broad, its basal ante- 
rior angle studded with a central longitudinal area of small black 
cusps. Anterior apical angle very slightly produced, smooth. 
Tarsus not scopulate ; tarsal claw furnished with 6 denticles on 
the basal half beneath. Coxa of pedipalp furnished on the inner 
side, on the basal portion of the central ridge, with the “ lyra,” 
consisting of 5 stout curved spines; three curving hairs towards 
the anterior portion, and one small bristle towards the posterior 
portion of the ridge. These 5 spines strike on the four stout, 
separate, isolated bristles above mentioned as situated on the 
mandible, which together form the “pecten.” These two struc- 
tures, the “lyra” and the “ pecten,” together constitute the 
stridulating-organ. 
Legs long and slender. Femora i. and ii. without spines; iii. 
with a few spiniform bristles; fourth pair of legs absent. Patella 
1, 1, & ii. without spines. Tibie i. & ii. with one or two spines 
beneath ; iii. with a double row of 3—3 on either side. Pro- 
tarsi i. and ii. with 5 and 6 spines respectively beneath; iii. with 
numerous spines. (N.B. The number of spines on the legs is not 
constant.) ars with three claws, superior pair armed beneath 
with a double series of 5—6 denticles. Inferior claw long. 
Tarsi 1. and ii. scopulate. 
Abdomen long-narrow. Spinners four. Posterior pair as long 
as abdomen, three-jointed ; basal equal in length to the second 
joint; terminal joint longer than the second. Anterior pair half 
as long as the basal joint of posterior pair, nearly the full length 
of one of them apart. 
Comparative measurements in millimetres.— 9. Carap. 10 long., 
Slat. Abd.17long.,9 lat. Cephl. area 6-5 long. Stern. 5 long., 
4 lat. Coxa of pedipalp 3:5 long., 2 lat. Pedes, long. i. 42— 
uu. 38—iii. 388—iv. abest. Artl.i., long. 4-8—2—9-5—3-75—8— 
775—5. Arti. iy. long.: abest. Postr. mam. 17 long. Arti. 
5—5—7 long. Antr. mam. 2°8 long., 2 sept. Mandib. 5 long. 
