ACROSOMA. 61 
longitudinal parallel rows beneath the tibia of the first and second pairs. The colour of the legs is 
yellow-brown, the femora rather the darkest. 
The palpi are short, pale brownish-yellow. The digital joint is darker, and has its hinder extremity pro- 
duced into acurved horn-like somewhat obtusely pointed prominence directed outwards. The palpal bulb 
is of fair size ; the palpal organs are prominent and well developed, with processes whose points project 
at the fore end. 
The sternum is small, of a rather narrow-oval shape; the legs are articulated on its sides and in the same 
plane, the articulations being covered in a shield-like form by the projecting margins of the thorax. 
The abdomen is about double the length of the cephalothorax, and narrow; the hinder extremity truncate in a 
slightly curved form ; the sides are nearly parallel, being very slightly curved, the convexity of the curve 
directed outwards ; the fore end fits up close upon and over the thorax. It is of a dull luteous-yellowish 
hue above, with an incomplete blackish marginal band on each side, whose outer edge is white. The 
hinder extremity has a blackish, more or less diffused spot or patch above. The underside is yellow- 
brown, more or less suffused with blackish; at the posterior extremity is a somewhat conical promi- 
nent point on each side, above which are two transverse ruge. ‘The spinners, which are short, compact, 
and but little prominent, are placed more than one-third of the distance from these ruge to the anterior 
extremity of the abdomen. 
Hab. Panama, Bugaba (Champion). 
Several examples. 
Acrosoma longicauda, sp. n. 
Adult male, length 24 lines, length of the abdomen 12, that of the portion beyond the spinners 1} line, 
The cephalothorax is of a yellow-brown colour, and its surface is granulose and thinly clothed with short hairs, 
The normal grooves and indentations are fairly defined, and the posterior margin is a little turned up. 
The eyes of the central group form a square. 
The legs are short, 4, 1, 2, 3, of a brownish-yellow colour, the femora of the first three pairs being of the same 
hue as the cephalothorax. They are furnished with short hairs but are destitute of spines, and the under- 
sides of the femora are slightly granulose. 
The palpi are short, the palpal bulb rather large. The digital joint has its hinder extremity produced into a 
strong, curved, bifid, obtusely pointed prominence directed outwards; the palpal organs are highly deve- 
loped, and have several prominent corneous lobes and processes. 
The sternum is elongate-oval or somewhat subtriangular, convex, and granulose, similar in colour to the 
cephalothorax. 
The abdomen is narrow, oval, truncated before, and fixed to the cephalothorax by a short pedicle. Its hinder 
extremity is produced into a long caudiform prolongation, whose posterior portion is segmented, or at any 
rate has the appearance of it from two strong transverse constrictions, the hinder edges of each of which 
overlap the next segment. The extreme end is rather dilated and truncate, with four subconical pro- 
minences, one at each corner. (I suspect that the segments noted above are so far real segments that the 
caudal portion can be elevated or depressed, like a true tail. They are probably an extreme development 
of the transverse rugs, observable very distinctly in some, and slightly in most, spiders at the extremity 
of the abdomen—to speak more correctly, they are perhaps a reversal to, or may be the survival of, an 
original segmented condition common to the far off progenitors of the Araneidea.) The whole upper 
surface of the abdomen is coriaceous, finely granulose, and covered with short hairs; it is of a pale 
yellow-brown colour, obscurely marked on the upperside and also along the underside (this part being 
granulose) with blackish ; on the upperside near the middle are two pairs of reddish-brown oval spots, 
margined narrowly with yellowish, and forming an oblong figure, the posterior pair being much the largest. 
The sides of the abdomen are longitudinally rugulose. The spinners are in a strong sheath-like 
prominence, and placed scarcely more than one-fourth of the way from the fore extremity towards the 
hinder part of the caudal prolongation. 
Hab. Panama, Bugaba (Champion). 
