Gatti) Marine Laboratory ^ St. Andrews. 5 



the ventral border — tlie dorso-lateral continuatiou of the lip 

 bearing the first group of branchiae. The tentacles liave the 

 normal strnctuieand a deep groove. The segment fuUoMing 

 the foregoing has no distinct shield, the anterior edge 

 ventrally forming a free border and ending laterally on cacli 

 side in a rounded free flap. A second Iree anterior rim 

 follows, also ending laterally in a rounded flap, opposite the 

 second branchia. In the middle line is a large shield, which 

 sometimes indents the segment behind it. Opposite the third 

 branchia and the first bristle-tuft is a third rounded external 

 flap, which passes further dorsalwjird than the other two. It 

 abuts on a narrower shield than the one in front. 



The body is enlarged anteriorly and gradually tapered 

 posteriorly to the terminal anus. Dorsally it is rounded, 

 ventrally are about ten to twelve shields anteiiorly, and 

 then a median gioove passes to the posterior end. Seventeen 

 pairs of vertical flattened setigerous processes occur ante- 

 riorly, the first being in a line with the la^t branchial tuft. 

 The bristles are dull golden and in two series — a longer and 

 shorter ; the former are deeply inserted, have shafts nearly of 

 uniform diameter throughout, and have comparatively sliort 

 tapering ti| s with wings winch are broad at the commence- 

 ment, but taper off distally. The condition of the tip, 

 however, is variable, apparently from injury, since many are 

 short witli short and broad wings and tips that taper litile, 

 the result, in all probability, of injury and repair. The 

 shorter series has winged and tapering tips, though a few at 

 the edge present short (broken?) tips with broad wings. A 

 minute papilla occurs on the ventral side of the setigerous 

 process, from the second to the eighth bustled segment. 

 Moreover, just below the papilla a little flap is developed at 

 the dorsal end of each hook-row, and sloping backward 

 behind it from the first bristled segment (which has no 

 hooks) to the last, where, however, it is less distinct. No 

 hooks occur opposite the first bristle-bundle ; a single row 

 is present on the next foot, and for several feet thereafter, 

 but the ei<;htii has two rows. The hooks have in lateral 

 view^ about four teeth above the main fang, and the posterior 

 outline curves forward to the crown and has a projecting 

 process of the ba;-e inferiorly. The base has a gentle curve, 

 slopes from behind dowuwurd and forward, and an eminence 

 occurs on the anterior curve below the main fang. Striae 

 pass from the teeth on the crown to the posterior border 

 of the neck. The broad ridges for the hooks are large 

 in the bristled region, but thereafter they diminish to 

 short lamellfCj and then to low ridges toward the tail. The 



