PRAXILLELLA PILETERMISSA. 329 



stricted behind where it joins the first bristled segment. The first three bristled segments 

 are nearly equal in length, the first being the shortest in the preparations, and each bears a 

 tuft of bristles and a golden spine, which in large examples is very powerful, though not long. 

 It has a stout, striated shaft, enlarges from a slightly narrowed base, and again diminishes 

 to the tip, which is likewise finely striated (longitudinally) internally, and often has a 

 distinct curvature at the tip. 



The first three bristled segments do not present marked glandular areas, but the fourth 

 has a narrow ring at the anterior part of the segment, and in front of the bristle-bundles. 

 The fifth, sixth, seventh, and eighth segments have broader belts of glandular tissue, which 

 occur in the same part of the segment and envelope the ridges for the hooks. The ninth 

 foot occurs at the posterior part of the segment, and is glandular, as are those which 

 follow — as far as the nineteenth. The four terminal segments have a glandular ridge on 

 each side, the last forming, by nearly coalescing with its neighbour, a kind of ring. 



The six segments in front of the terminal funnel differ in shape from the preceding, 

 being narrow in front and wider posteriorly, the elevation for the hooks or the corre- 

 sponding glandular areas without hooks being placed on the prominent angles posteriorly. 

 The seventeenth and eighteenth bristled segments, that is, the first two of this series, are, as 

 a rule, those best marked, though the condition varies in the preserved examples. The 

 bristles of these segments (Plate CIX, figs. 13 and 13 a) are in two groups, the larger 

 being capillary bristles with fairly stout shafts and somewhat narrow wings at the finely 

 attenuate tip. The other group consists of capillary bristles with more slender shafts 

 and more finely attenuate tips. In the example from St. Magnus Bay the last tuft of 

 bristles in front of the funnel had a mere trace of a wing, with the edge faintly serrated. 

 The anal funnel (Plate 0, fig. 21) appears to vary considerably in regard to the 

 number and the shape of the cirri, those with few cirri having them broad at the base 

 and more distinctly conical, whilst they are more filiform in those in which the cirri 

 approach thirty in number, though in one from North Unst the sixteen separate cirri are 

 filiform. The elongated cirrus is in the mid-ventral line. The anal cup is comparatively 

 shallow, with the anus often on a slight cone in the centre. In two large Hebridean 

 examples the cirri of the funnel are all short, and twenty-seven in number. In another 

 large form procured in the ' Porcupine ' off Cape Guardia the funnel has no long cirrus ; 

 the number of cirri is thirty-seven, and the anal process is conspicuously ridged or folded. 

 A small specimen from St. Magnus Bay (1 00 fathoms) had a very long, filiform, mid-ventral 

 cirrus. Occasionally the vent projects as a conical process, similar to what Arwidsson 

 shows in his P. affinis. 



The hooks (Plate CIX, fig. 13 b) have a long, curved shaft, tapered at its base and 

 dilating as it passes upward to the shoulder, which forms a prominent hump posteriorly 

 and a slight one anteriorly. It then contracts to the neck, above which the distal 

 region dilates, and ends in a broad, heavily-armed crown. The main fang leaves the 

 throat nearly at a right angle, curves slightly downward, and ends in a sharp point. 

 Six to seven teeth in a diminishing series occur on the crown. The interior of the 

 shaft is striated, and the striae are continued into the neck, where they are somewhat 

 oblique inferiorly, but longitudinal toward the crown. The gular bristles come off close 

 to the main fang, and curve forward and upward on each side of it. The anterior 



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