826 Mr.H.D.S8. Goodsir on new species of Crustaceans. 
jointed. Eye situated behind the rostrum, rhomboid, transverse. 
Posterior pair of legs showing only one joint from the posterior 
and lateral edge of the body, armed on the lateral edges with 
strong spines, the two terminal spines being strongest. 
Description.— Body ovoid, rather dilated, anteriorly quite 
smooth. The anterior segment of the body as large as the 
whole of the remaining segments, and having the lateral edges 
surrounded with a narrow border, This animal is very active and 
swims about with great rapidity. It is exceedingly minute, not 
being larger than a mere point. 
Sterope armatus. Plate XI. fig. 9. 
Rostrum very prominent, rounded, and one-third the whole 
breadth of the body ; antennze six-jointed, and armed at the ex- 
tremity and on the anterior edge with a series of robust long 
spines. Eye not apparent. 
Carrillus oblongus. Plate XI. fig. 12. 
Rostrum one-eighth the breadth of the whole body, prominent, 
rounded at the extremity, with the eye very small, and situated 
almost upon the anterior edge ; anterior edge of body hollowed 
out on either side of the rostrum. Antenne clavate and eight- 
jointed, very little ionger than half the breadth of the body, un- 
armed, last joint pointed. Abdominal legs delicate, and armed 
at the extremities only with one or more spines. Abdominal 
segments of body taper gradually. 
Sterope interruptus. Plate XI, fig. 10. 
Rostrum prominent, one-tenth the breadth of the whole body, 
poimted. Eye large, and filling almost the whole of the rostrum. 
Anterior edge of the body hollowed out on either side of the 
rostrum. Posterior thoracic legs strong, spined, and serrated on 
the external edges. Three strong short spines arise from each 
side of the abdominal portion of the body, and a strong pedicle 
armed with three spmes arises from the posterior edge of the 
last abdominal segment on each side of the mesial line. 
Zaus spinatus. Plate XI. fig. 1. 
Antenne three-jointed. <A spine arises from the anterior edge 
of the carapace on each side of the mesial line, one from the base 
of each of the antennze. Abdominal pedicles three-jomted, distal 
one armed at its extremity with three robust strong spines, the 
central ones longest. 
EXPLANATION OF PLATE XI. 
Fig. 1. Zaus spinatus, magnified. 
Figs. 2, 4, 5, 7, 8. Organs of locomotion. 
Fig. 6. One of the first antenne. 
