52 THE VOYAGE OF H.M.S. CHALLENGER. 
must perhaps partly be attributed to inaccuracy ; they may have been occasioned by the 
circumstance that Béhm’s material was much more limited than mine. Bohm doubts 
whether he has a male example or not, whereas I had a dozen at my disposal, five of 
which were furnished with eggs. 
Nymphon perlucidum, n. sp. (Pl. V. figs. 6-10). 
Diagnosis.—Body and legs very slender, pellucid and smooth. Second joint of the 
palpi elongated, much longer than the third. Second joint of the feet more than twice as 
long as the third. First tarsal jomt uncommonly short. Accessory claws. 
Description.—This is a very small and a very fine species, the most transparent 
form of Nymphon I ever observed. The proboscis is robust, yet very long, much longer 
than the first segment of the body. There is no interval between the lateral process 
of the ovigerous leg and that of the first true leg, but the intervals between the other 
lateral processes are very large. The abdomen is small. The eyes are obsolete: a very 
small tubercle without pigment is all that is to be seen. 
The mandibles have the first jomt as long as the proboscis, the second small with 
very long claws, the immovable claw is strongly curved at the extremity. The number 
of spines on these claws is much more limited than in any of the other species of 
Nymphon, being four on the movable claw and only five on the immovable one. 
The mandibles are scarcely hairy: a few stronger hairs are observed at the end of the 
first joint, and again at the origin of the movable claw. 
The palpi are not very long, once and a third as long as the proboscis. They are 
slender, the second joint being comparatively much longer than the third joint, and 
nearly as long as the three last joints together. They are covered with very small hairs. 
The ovigerous legs are short: 44 mm. in a male of 5 mm.; the fifth joint is the 
longest, considerably swollen at the extremity ; the sixth is a great deal shorter and 
feebly bent; the four last joints are very short, the claw being half the length of the last 
joint. The different joints are covered all over with very minute hairs. The spines of 
the four last joints are broad, but very small and almost show the hand form (PI. V. 
fig. 9). They are not very numerous, their numbers being respectively 7, 4, 4, 5. The 
claw is furnished with some small spines (PI. V. fig. 8). 
The legs are slender, but not very long, only two and a half times as long as the 
body. The second joint is twice as long as the first and third; the fifth is longer than 
the fourth, and the sixth is the longest. The two tarsal joints are highly characteristic 
on account of the shortness of the first, and the strong spines placed along that side of 
the second which is opposite the claw. *The length of the accessory claws is not half the 
length of the claw. The legs are covered with small hairs, stouter ones being placed on 
the fifth and sixth joints, and at the end of the joints. I have figured the two tarsal 
joints in fig. 10, Plate V. 
