376 W. C. M'INTOSH ON BRITISH ANNELIDA. 



greater part of the surface of the scale is densely covered with minute and rather blunt 

 horny spines, which toward the free edge become large acute processes. The extreme 

 roughness of the surface of the scale readily causes mud and debris to lodge. In shape 

 the scales are for the most part reniform. They therefore present a marked difference 

 from those of the Zetlandic specimen (which show small papillae over the surface, 

 a few large pale examples only projecting beyond the free edge, and eight or nine sub- 

 globular processes at intervals in the same region), as well as from the form described 

 by Malmgren. 



The dorsal branch of the foot bears a somewhat dense mass of rather short pale 

 bristles with a slight curvature. The tips are comparatively short, and by no means 

 acute. One of the longer forms is sketched in PI. LXVII. fig. 12. The ventral division 

 has translucent bristles with moderately long shafts. The tips of the superior series 

 (PI. LXVII. fig. 13) are long and somewhat taper, with rather distant rows of long 

 and distinct spines, the end being minutely bifid. The tips gradually become shorter 

 and stouter inferiorly (fig. 14), the strongly curved terminal division, and the inferior 

 process, with its characteristic angle of incidence, being noteworthy. Some of the 

 latter bristles show traces of a curve outward between the secondary process and the 

 first row of spines. Toward the ventral border the secondary process diminishes with 

 the general size of the bristle ; there is a minute trace, however, in almost all. It is 

 difiRcult to separate these bristles from those of the larger example (with smoother 

 scales) from Shetland. 



Malmgeenia castajs^ba', n. sp. Dredged by Dr. Gwyn Jefiferys ofiF North Unst, Shet- 

 land, in 90-96 fathoms, in 1867, and again, in 1868, on Spatangus purpureus (near the 

 mouth), in 85 fathoms, on shell-sand. The same gentleman procured it in 80 fathoms, 

 oflF Valentia (S.W. Ireland), and 110 fathoms off the Blasquet. It has also been found 

 in the Channel Islands. 



Two species only are mentioned by Malmgren as having smooth palpi, antennae, 

 tentacles, and cirri, viz. Melcenis loveni and Enipo kinhergi. The first is easily distin- 

 guished from the present form by the fact that the scales leave the centre of the dorsum 

 uncovered anteriorly, while in the second the scales occur only on the anterior part of 

 the body. Both diverge much in the structure of the bristles. In this form the head 

 is slightly pinkish in life, as is also the proboscidian region. Two eyes are situated 

 near the posterior border, and two laterally on the anterior prominence. The tentacle 

 is moderately developed, and has a slight enlargement below the tapering tip. The 

 antennae have brownish pigment a little above the base. The scales are fifteen pairs, 

 smooth to the naked eye, but under the microscope showing some minute papillae in 

 the line of the pigment, and a more distinct group opposite the curve or covered 



' The generic name is in honour of Dr. Malmgren, of Helsingfors, the author of the valuable ' Annulata 

 Polychseta Spetshergiae,' &c. 



