64 ARANEIDEA. 
Abdomen somewhat quadrate, longer than broad, or, at least, its width at the posterior extremity, exclusive 
of the prongs of the two hinder corners, almost equal to its length. The anterior extremity is concave 
to admit the thorax, and is nearly equal in width to the cephalothorax, and each of its corners is pro- 
longed into a sharp tapering spine of no great length, directed forwards in the same plane as the level 
upper surface of the abdomen ; each hinder corner is produced into a considerable and strongly divergent 
prominence directed obliquely outwards and upwards, the extremity of which is trifid—the central limb 
largest, and the inferior one, which is directed rather downwards, smallest, each limb tapering, cor- 
neous, and ending with a dark spiny point; on each lateral margin of the abdomen in advance of the 
hinder prominence are two small slightly curved spines in a longitudinal line, the anterior one on each 
side being nearly halfway between the fore and hind corners. The abdomen is of a cream-yellow colour, 
margined laterally with dusky brownish, and has a double row of dark impressed spots on each lateral 
margin, and six larger reddish-brown ones in three pairs in the median line of the fore part of the 
upperside ; the posterior part, which is of a triangular form, is also cream-yellow, marked with four 
longitudinal rows of small impressed dark points; the sides are longitudinally rugulose, dark brown, with 
two or more yellow spots along each rugulosity. The spinners are in the usual, almost circular sheath-like 
prominence. Underside dull olive-greenish-yellow-brown ; genital prominence strong and of character- 
istic form. 
The falces, mawille, labiwm, and sternum are similar in colour to the cephalothorax. 
Hab. Panama, Bugaba (Champion). 
Acrosoma fericulum, sp. n. 
Adult female, length slightly over 14 line, length of the abdomen 1 line. 
Cephalothorax dull yellowish-brown, less flattened, or rather more regularly curved than in some other species 
of the genus; normal grooves and indentations slightly marked. 
Eyes of the central group on black spots, forming a square whose anterior side is shorter than the others. 
Legs short and slender, 4, 1, 2, 3, of a yellow-brown colour, some of the joints partially or wholly suffused or 
marked with dark brown and blackish. 
Sternum convex, heart-shaped, deep bistre-brown, and devoid of lateral eminences. 
Abdomen large, double the length of the cephalothorax, and attached to it by a short pedicle. It is of a some- 
what subtriangular form, bluff and rounded behind. On the upperside on the lateral margin are three 
pairs of sharp, slightly curved, outwardly directed, thorn-like spines, these being continuations of the abdo- 
minal prominences ; the anterior pair of spines are a short distance behind the fore extremity, the middle 
pair rather nearer the hinder than to the anterior pair, the hinder pair a little way from the posterior 
extremity and rather shorter than the others, which are of nearly equal size, the middle pair being 
perhaps the longest. On each side of the rounded posterior part of the abdomen is another short spine. 
The abdomen is of a yellow-brown hue, marked above with some small round, reddish, cicatricose 
spots, and three whitish-yellow tubercular spots in the form of a triangle about the middle, the largest 
spot (the apex of the triangle) in front; the spines are black; and there is a whitish longitudinal stripe 
behind each of the three pairs of prominences. The sides are rugulose and marked with two vertical dull 
yellowish stripes. Spinners very prominent, at the extremity of a large subconical sheath-like eminence, 
a little way behind the middle of the underside. Genital aperture not very conspicuous, but of charac- 
teristic form. 
Hab. Guatemaua, Menché, Yzabal (Sarg); Panama, Bugaba (Champion). 
The above description is chiefly taken from the Bugaba specimens. In Mr. Sarg’s 
collection there is an example from Menché, and another from Yzabal, both immature 
males ; these have the three larger pairs of spines on the abdomen rather straighter, 
and the fourth pair obsolete. 
