of the North Atlantic and of North- Western Europe. 679 



2. Sarsiella globulus, n. sp. 

 (Plate LX., figs. 5-17.) 



Seen from the side the outline is circular, the height equal to the length 

 exclusiye of the posterior projection, which is longer and situated higher on 

 the hinder margin than in the last species. The margins from above and below 

 this projecting process form a complete circle round the ventral, anterior, and 

 dorsal margins ; the surface of the valves round, the sides is more evenly convex 

 tlian in S. capsula, but an oblique central portion is flattened and margined by 

 riblets, the lower of which commences in front, a little within the anterior border 

 and slightly below its centre; it thence passes downwards and then backwards 

 towards the conical posterior process, at some distance from the base of which it 

 suddenly bends upwards towards the dorsal margin, which it does not quite reach; 

 the second riblet commences anteriorly a little above the first, and passes in an 

 oblique direction across the valve towards the dorsal margin near which, and at no 

 great distance from the termination of the previously described riblet, it ends in a 

 blunt upraised point ; the surface is everywhere punctated. Seen from below, the 

 general form is oval, but towards the hinder extremity the outline becomes 

 irregular owing to the prominence of the rib-bordered areas already described, 

 while in the centre behind the posterior conical process is seen exserted. Greatest 

 length, 2 mm.; height, 1-9 mm. 



The antennules (fig. 8) resemble in every respect the same organs in S. capsula, 

 except that the second joint has, besides the seta on the front margin, about 

 three minute spinules, and one similar spinule on the hinder margin. The 

 mandibular palp (fig. 10) has a much longer seta on the first joint in addition to 

 the short spine-like setse, and the terminal joint has a small secondary unguis in 

 addition to the large unguis. The first maxillse (fig. 11) have four lateral lobes, 

 two of which bear six setse, the third three, the fourth two ; the extremity of the 

 limb is armed as in ^S*. capsula, but the terminal joint is rather longer. The 

 second maxillae (fig. 13) consist of three lobes and a single-jointed palp; the first 

 lobe bears one, the second three, the last nine setse ; the palp ends in three setse, 

 and there is another seta on the limb at the base of the palp. The caudal laminse 

 (fig. 17) bear seven ungues, which are remarkably long and slender, and the last, 

 only proportionately longer than the preceding. 



OfP the coast of Soudan, North Africa, in 2333 metres, "Talisman," July 15, 

 1883, a single specimen (Marquis de Folin). . . 



5C2 



