PYONOGONIDA. 51 



The Body is well built with the lateral processes rather widely separated, and 

 traversed by three very prominent pyramidal ridges which conceal the segmentation. 

 These ridges are directed backwards to a very slight extent and excavated posteriorly ; 

 it is in the hollow thus formed that the segmental divisions may be seen. Three ridges 

 are equally prominent ventrally, but they are not produced to a median point. 



The Cephalon is not very much expanded, and a neck is not noticeable. 



The Ocular tubercle is stout, not as tall as any of the three transverse ridges, and 

 bears four well-developed eyes, above which it terminates in a short cone. 



The Abdomen is rather long, directed obliquely upwards, not separated from the 

 trunk by an articulation, and terminating in a blunt point. The cephalon bears a 

 small blunt tubercle at its anterior margin on the outer side of the base of the chelifori, 

 a pair of similar tubercles occur dorsally at the extremity of the lateral processes ; 

 smaller ones also on the first coxae with traces of them on the second. The length of 

 the body is 12 mm., its extreme width is 7 mm. The entire body is scabrous, a feature 

 most distinctly noticeable on the transverse ridges and the abdomen. 



The Proboscis is large, rather pyriform in shape, and measuring 10 mm. in 

 length. It is movably articulated to the body on a large base, and widens slowly for 

 one-third of its length where it is very slightly constricted ; it is then enlarged 

 again, and tapering very slightly, ends in a rather broad round point, the triangular 

 mouth being of moderate dimensions. The proboscis is smooth, and its distal two- 

 thirds are marked by three pairs of longitudinal bands, transversely divided near 

 the tip. 



The Chelifori are rudimentary and lie close together above the proboscis. The 

 scape is short, slightly curved and enlarged distally ; the chelae are well developed, 

 as long as the scape, one half of their length is taken up by a bulbous palm ; the 

 fingers are slender, quite smooth and much curved, but those of the two» appendages 

 are not exactly alike. With the exception of the fingers the entire appendage is 

 scabrous. 



The Palps arise laterally just outside the chelifori, and comprise nine joints 

 (fig. 3a). The first is short and stout, the proportions of the second and fourth are 

 as 8 to 11, the third being but little longer than the first; the remaining five are 

 short and sub-equal, the middle one and the last being a trifle the longest, together 

 they scarcely equal the length of the fourth. The fourth joint possesses a prominent 

 tubercle with a glandular opening at two-thirds of its length. The entire appendage 

 is more or less plentifully clothed with very minute spinous setae ; these however are 

 only conspicuous on the ventral margin of the five terminal joints and at the end of 

 the terminal one. 



The Oviger is ten-jointed and rises ventrally immediately in front of the first 

 lateral process, and appears to be that of a female (fig. 3b). It is not fully developed. 

 The first joint is short and stout, the two following are twice as long and sub-equal, 

 the third having the usual oblique termination. These three joints form a natural 



