630 
DR. RUDOLPH YON 'WILLEMOES-SUHM ON A 
running out at either side into a spine, which is the first and largest of a series of 
twelve spines bordering the outer edge of the head-shield. The mouth (Plate XL1X. 
fig. 1, o) is a very small opening on a round papilla placed near the posterior edge of 
the lower surface of the head. It is covered by a pair of rudimentary maxilla?, with a 
sort of labium between them, and by two pairs of inaxillipeds (Plate XLIX. fig. 1 ,mx). 
A groove, the borders of which are adorned by series of one larger and five smaller teeth, 
runs backwards to the mouth along the middle line of the lower surface of the head. 
Fig. 3 gives a lateral view of the under surface, which is more easily understood from a 
figure than from the description. At the fronted border, separated by a distance of 
about 7 millims., there are two antennae 26 millims. long. The antennae consist of two 
elements, of which the proximal is longer than the distal, which is enlarged at the end, 
and bears a very small recurved claw. 
Tiie Thoracic region consists of six segments. The first of these bears the smaller 
pair of inaxillipeds, and shows on its inferior surface an elevation, which is the 
genital papilla. The second segment is wider than the first, and bears two pairs of 
appendages — the longer inaxillipeds and the first pair of ambulatory legs, which are 
more slender than the other four pairs, and have the proximal joint not so strongly 
denticulated ; they are also inserted a little within the other four pairs, and they were 
held by the animal (which was still living when brought up) in the characteristic 
position of the accessory legs of the pycnogonid Nymjphon. The eggs, which in this 
case are not held by the two rudimentary lamellae near the vulva, were attached to 
these legs. The next four segments of the thoracic region bear each one pair of 
ambulatory legs, making, along with the pair on the second thoracic segment, five pairs 
in all. Of these the third pair is the longest ; this is followed in length by the fourth, 
then comes the second, then the fifth, and finally the first. The length of the longest 
limb is 69 millims. The legs consist of four joints, showing denticulations and 
hairs. At the point of attachment of the proximal joint to the body no coxa can be 
distinguished. The leg is inserted into the thoracic segment, in the same manner as in 
Phronima. In the limbs of the third, fourth, and fifth pairs the proximal joint is 
terminated distally by a large spine. The second joint is very small in the limbs of the 
first pair, and still smaller in those of the fifth. In the limbs of the fifth pair the third joint 
is also remarkable, as it bears at its distal end a large tuft of straight hairs ; and the fourth 
is more enlarged than the corresponding joint of the other limbs, and terminates in a 
stronger and more recurved claw. In Phronima the fifth pair of ambulatory legs, which 
corresponds with the third pair in the present form, presents the same modification. 
The enlarged distal terminations of the limbs and of the antennae are not, like the 
remaining part of the appendages, transparent, but are of a milk-white colour, produced, 
I believe, by glands in their interior analogous to the glands in the enlarged claw of 
Phronima. To the bases of the second, third, and fourth pairs of legs three pairs of 
gills are attached. 
The Abdomen consists, as in Phronima , of five segments, the first three of which bear 
