South African Hydrachnids. 453 



it is that in Eulais occulta Sig Thor, 1899 (29). The eye-bridge 

 (figs. 17 and 18) is broad, simple, without special marks, convexly 

 projecting anteriorly, and with the posterior margin straight or 

 curved. The hair-pores are not situated in the bridge but in the 

 inner margin of each capsule (fig. 17, h). The muscles are attached 

 to the inferior side of the bridge (fig. 18, m). The two pairs of 

 eye-lenses have the same shape and situation as in Eulais Latr., 

 the anterior ones being stalked and the posterior ones curved and 

 ellipsoid. 



Maxillary Organs. — The maxillary plate (fig. 16) is shaped as in 

 most of the species of Eulais Latr. , and exhibits no very remarkable 

 characters. The shape of the mandible may be seen in fig. 19. 



The maxillary palps (figs. 20 and 21) are, as already stated, 

 extremely thick and short ; the second segment is about 0*21 mm. 

 thick, almost a third of the total length of the palp ; the third 

 segment is 0*17 mm. thick. The lengths of the 5 palpal segments 

 (counting from the first to the fifth) are about 0-08 -f 0*17 + 0*13 

 + 0*24 + 0"13 mm. The third segment possesses (like the second) 

 on the inner side at the distal end 4 short thick spines, besides 

 4 others in the middle (fig. 20), 



The inner side (fig. 20) of the fourth segment bears in a row only 

 2 longer and 3 short feathered spines, and at the distal end 3 short, 

 broad, feathered ones. The otiter side (fig. 21) has only 1 long 

 ensiform and 1 extraordinarily thick and strong spine at the distal 

 end. A similar spine exists near the proximal end of the fifth 

 segment. The thick distal spine of the fourth segment recalls to 

 mind the distal process in Tiphys Koch (7, 8), Acercus Koch, 

 Forelia Haller, Curvipes Koenike (19), Lehertia Neuman (11), and 

 other genera. Probably a prehensile function, like that of claws, is 

 to be attributed to these two spines in Gapeidais. 



The fifth segment is not pointed at the distal end, but enlarged,, 

 and possesses here about 6 spines. 



Legs. — The 3 anterior pairs of legs have the same shape as in 

 Eulais Latr., the second and third having many, the first pair but 

 few swimming hairs. The fourth pair (fig. 22) is extremely thick 

 (the third segment being 0*33 mm. in diameter), but otherwise of the 

 same structure as in Eulais Latr. The fourth leg is almost twice 

 as thick as the other legs and thicker than the maxillary palps ; 

 there are no swimming hairs, and only a few small spines. The 

 claivs are short, but normal and bifid. 



More considerable external differences between the two sexes do 

 not occur in the species. 



