REPORT ON THE CUMACEA. 47 



in the genera Cyclaspis and Paralamprops, as described above. The strong adductor 

 muscles filling the concavity of the body are connected by a broad chitinous tendon, to 

 which two other diverging muscles are affixed posteriorly. The rotatory muscles 

 constitute several strong bundles arising from the inside of the carapace dorsally, and 

 joining successively a very long and slender tendon, which is affixed to the inner edge of 

 the body immediately behind the molar process (cf PI. VIII. fig. 1 ). 



The first pair of maxillas (fig. 8) exhibit the usual two masticatory lobes, springing 

 from a rather thick and muscular basal part. The refiexed palp is distinctly developed, 

 and about as long as the outer masticatory lobe. It bears at the tip two diverging setae 

 of somewhat unequal length. 



The second pair of maxillas (fig. 9) agree on the whole rather well in structure with 

 those in the genera Cyclaspis and Paralamprops, as described above. 



The maxillipeds (PI. VII. fig. 2) have the basal part rather large, and provided with 

 a ridge running along the lower surface and strongly denticulate in its anterior part. 

 The masticatory lobe exhibits the usual structure and has a row of ciliated setae continued 

 along the inner edge of the basal part. Of the joints composing the terminal part, the 

 second (carpal) is, as usual, the largest and rather expanded ; it has at the outer corner a 

 very strong and elongate plumose seta pointing anteriorly, and along the inner edge a 

 row of short, slightly curved spines, which are densely ciliated in the middle (fig. 4), 

 besides numerous, partly plumose bristles. The jjenultimate joint is much smaller, and 

 provided at the end with two strong anteriorly curving setae. The terminal joint, finally 

 (fig. 3), is conical, with two unequal spines at the tip, and one or two simple hair-like 

 bristles. 



The branchial apparatus affixed to these limbs (fig. 1) is very fully developed, and 

 the epipodite-plate, especially, is very large and of a distinctly navicular form. The gill- 

 lobules are digitiform, and arranged in a slightly spiral series along a thin flexuous 

 lamella issuing from the inner edge of the epipodite-plate, and partly doubled over it. 

 They rapidly increase in length from behind forwards, the posterior lobules being very 

 small and knob-like ; from the bottom of the concave surface of the epipodite-plate, 

 moreover, a single somewhat larger gill-lobule, pointing anteriorly, arises. The 

 exopodite is scarcely half as long as the epipodite, and constitutes a narrow anteriorly 

 directed plate, broadest at the base and gradually tapering to a narrow, somewhat curved 

 neck, which again expands into a triangular lamella bordered by a thin narrow membrane, 

 The inner straight edge of this lamella lies in close contact with that of the lamella of 

 the other side, both together forming an imperfect tube, which can be exserted beyond 

 the tip of the pseudorostral projection (cf PI. VIII. fig. 1), and serves for the expulsion 

 of the water introduced into the branchial cavities. 



The first pair of gnathopoda (fig. 5) are rather slender and exhibit at the base, affixed 

 to the short coxal joint, a quadrangular lamella, to the posterior edge of which a dense 



