. REPORT ON THE PYCNOGONIDA. 8 



mutilated, with only five legs — was collected during the voyage of the Challenger. This 

 specimen is, I think, a full-grown male. The body is extremely slender, with very large 

 intervals between the lateral processes for the insertion of the legs. The cephalo- 

 thoracic segment is rather short, about twice as long as the first true thoracic segment ; 

 the second thoracic segTnent is a little longer than the first, and the third is, again, a little 

 shoi-ter. The proboscis is long, inserted ventrally, far back between the two ovigerous legs. 

 It shows a little swelling at its base, in the middle, and again at the extremity. The 

 mouth is small and triangular. The abdomen is short and directed somewhat upwards. 



At the base of the mandil:)les the front part of the cephalothoracic segment is 

 for a short distance cloven in the middle. Immediately behind this cleft the blunt 

 oculiferous tubercle, with its four dark eyes, Ls placed. The basal joints of the mandibles 

 diverge considerably, and extend beyond the front of the proboscis. The end of this basal 

 joint, which is directed forwards, terminates in a pointed appendage, and laterally, under- 

 neath the end of this appendage, the short second joint is attached. This has the form 

 of a bird's head with the small pincers as jaws. The inner surface of these pincers is 

 smooth. The first joint towards its extremity and the whole surface of the second joint 

 are covered with numerous long hairs. 



The ovigerous legs are inserted close to the base of the proboscis; they are six-jointed; 

 the first joint is small, the second about half as long as the proboscis, the third nearly as 

 long as the proboscis, the fourth half as long as the second, the fifth a little shorter than 

 the fourth, and the sixth extremely small. All the joints are furnished with numerous 

 small hairs ; those on the two last joints are a little longer, but still extremely slender. 



The first joint of the legs is small, nearly as long as the lateral process, the second joint 

 is more than twice as long as the first, the third joint nearly half as long-as the second, 

 the fourth is as long as the trunk with the abdomen, the fifth is but little shorter, the 

 sixth is as long as the whole length of the body, the seventh is short, and the eighth 

 nearly as long as the second joint. The part of the eighth joint facing the strong claw 

 has a distinct shoulder, furnished with spines and small hairs. The first joint of the 

 leg bears at the distal extremity, on both sides, a strong conical protuberance ; the second 

 bears a still larger one ventrally, and another at the distal extremity ; the third, too, 

 is furnished with one. Besides three strong protuberances at the distal extremity, the 

 longest of which is placed between the two others, the fourth joint has three other 

 protuberances placed laterally on the joint ; one of these is placed in the middle, the two 

 others on the other side at ec[ual distances from the middle one. The protuberances at 

 the extremity of the joint are much larger than the others found on the joint. The 

 latter have, moreover, a slender spine at the top. The armature of the fifth joint is 

 nearly the same as that of the fourth. The sixth joint is furnished with numerous small 

 protuberances, bearing slender spines at the top. Distinct hairs are seen on all the 

 joints ; towards the fourth joint they grow stronger and denser. The sid.e of the last 





