308 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 5 



Pycnogonum hancocki Schmitt, 1934 

 Plate 47 



Pycnogonum hancocki Schmitt, Jour. Wash. Acad. Sci., vol. 24, 1934, 

 pp. 65-67, fig. 2. 



Diagnosis: Color light tan, with marked brownish reticular marks. 

 Three rounded tubercles on the middle line of the body. Legs rather 

 smooth, not with rounded knobs. 



Description 



Trunk: The 1st segment is equal to the 2nd, 3rd, and 4th com- 

 bined. Its greatest width over the lateral processes. The greatest width of 

 the 2nd segment is equal to the length of the first 2 trunk segments taken 

 together. The 3rd segment is about as wide as the length of the 1st trunk 

 segment together with % of the 2nd. Caudal lateral processes are fused 

 for part of their length. 



In a line behind the moderately high, rounded ocular tubercle are 3 

 rounded tubercles, each smaller than the ocular. That of the 3rd trunk 

 segment is the larger. The 1st is at the caudal margin of the 1st trunk 

 segment. The 2nd, a little larger than the 1st, has a similar position, and 

 on the last segment there is very slight indication of an elevation. The 

 distal margins of the lateral processes are slightly more coarsely granu- 

 lated than the rest of the body surface. 



Caudal segment: This is not conspicuous. It is about % the proboscis 

 in length and projects beyond the caudal line of the rather large lateral 

 process of the 4th pair of legs. 



Eye tubercle: The eye tubercle is about half as high as the median 

 dorsal tubercles and is provided with 4 dark eyes. 



Proboscis: This is nearly cylindrical, truncate, and a little narrower 

 in front than behind. It is about 21/4 times as long as its greatest width. 

 It is very slightly longer than the first 2i/^ segments taken together. 



Ambulatory legs: The distal margins of the 1st coxae of all the 

 ambulatory legs are a little enlarged, owing to a small nodule on either 

 side of the brown line of the reticulations which divide the white area 

 in two. At about the distal portion of the proximal half of the 2nd coxae 

 of the 2nd and 3rd legs there is a small nodule of size similar to the last 

 mentioned. The 2nd coxa of the 1st leg lacks this elevation, the 2nd coxae 

 of the 4th pair each have a pair of small rounded tubercles, one on the 

 mid-dorsal line, and the other transversely in the line a little behind the 

 median axis of the joint. The rest of the leg joints are uniformly granu- 



