to tlu' margin than to tho n-ntrc of the body. The)' are rather stron,;;-, and 1>_\- means of a deep annular furrow are divided 

 into a I'lne terminal segment, and a considerably stouter basal part. The male genital papilhe are prominent and situated as 

 usual. The hook-apparatus is of moderate si/.e and develojiment (PI. X'll, Hg. 17). The chief hook (uncinus) resembles that 

 of M. cirriferum in shape, but the shank is a little more curved, and the tine extremity is still more bent. The supporting rod 

 (manubrium) is only a ver\- little longer than the chief hook 'PL \TI, fig. 17). It is much bent, the stalk slender, and the 

 plate of the extremity is rather long and large; the terminal manual part is rather liroad. ami embraces the chief liook but 

 looseh'. (M' reserve hooks, I have found as many as 5. but usuall\- 4. The segmental glandulous sacks with their circular, 

 relati\ely small, ,ind little prominent openings, are situated between the parapodia level with their exterior margin. — The 

 mouth ami anus are but little removed from the margin of the bod)-, the latter less so than the former (PI, I, fig, 2 mu S: an). 

 The proboscis is well developed. The ventral nerve-cord is strikingl}' elongated, and has, thus, more resemblance to the usual ven- 

 tral cord in the .annelids. The cerebral ganglia and oesophageal commissures are but little developed, whereas the tentacular 

 nerve-ring is considerably so. — Host. An ted on celtica, Marenzeller. P'rom station 343. Norwegian North-Atlantic P^xped- 

 ition. Out ot the large number of this Comatula, obtained during the expedition, I ha\'e found not a few specimens (20 — 30) 

 ot this Myzostome. It is one of the more migrator)' species, as I have found specimens on the disk as well as on the bran- 

 ches. Complement.'il males not found. 



Mjjzostontu carpenleri, Graff (PL I, fig, 6, 7). 



A little ma)' be added to Graft's description of this species, if I ma)' judge froni the tew specimens I have examined, 

 viz. 3, but, of which, onl)' one was tolerabl)' well preserved. The length of the largest of m)' specimens was 4.25 mm. 

 whilst the breadth was somewhat more. A complemental male, adherent to the dorsum of the largest specimen, measured 

 1.5 mm. in length. The body is thick and not quite circular in shape, being longer than it is broad. The intestinal branches are 

 extended nearl)' to the margin of the Ijod)', and there is onl)' an extremely narrow, and luit little translucent, margin which 

 is not continuous, being interrupted between the final i:iair of cirri, and here, the margin is thick, and the ventrum arched 

 towards the dorsal side. The narrow translucent margin is partly interrupted, and is slightly indented in front of the month. 

 The cirri are 20 in number, situated in two series, one on each side, with a sniall interval at the anterior extremit)', between 

 the first i^air, and a larger interval between the last pair of cirri. The dorsal surface is but little arcuated between the an- 

 terior and posterior extremities, but is, on the contrary, considerabl)' arcuated laterall)'. On the dorsal surface, there are 

 several distinct, slight, ridges (PL I, fig. 6, PI. II, t'lg. 6 dr.), and on the ventral side, a very slighth' prominent obtuse longi- 

 tudinal keel (PL II, fig. 6). The hooks are strong (PI. \TI, fig. 18). The chief hook has a strong and curved point. The 

 supporting rod is not long, probabi)' somewhat shorter th;m the chief hook; it is relativet)' thick, not much curx'cd, and has 

 a rather short terminal plate. The manual part of the hook is somewhat longer ;uid not so broad as in the last mentioned 

 species, and it embraces the chief hook somewhat closer. (_">f reser\'e hooks, 3 were usually observed. The male genital 

 papillæ are feeblj' developed, and are but little prominent; the)' are situated on the exterior of the third pair of parapodia. 

 The little prominent apertures of the segmental glands are situated between the parapodia, nearer to the margin than them 

 (PL I, fig. 7, s., v.). On the exterior of each parapodium, aiul each gland, there is a depression, causing the niargin, here, to 

 be thinner, and more translucent. The mouth is situated at a small distance tVom the anterior margin (PI, I, fig. 7, mu.). 

 The cloacal aperture opens in a papilla situated just in the demarcation between the ventruni and dorsum (PL I, fig. 6, an.; 

 PL II, fig. 8, an.). As the \'entrum is, howe\'er, arched ujnvards towards the dorsal side, this species forms a transition 

 between species having the cloacal aperture on the ventrum, and those v\hich h;ive it on the dorsum. The colour white, shad- 

 ing somewhat towards yellow. — Host. Antedon dentata, Sa)', (Ant. sarsii, Diib & Kor.). The few specimens found ■3) 

 were all adherent to the disk, and the species belongs thus to the non-migrator)' ones. One complemental niale was found 

 adherent to the dorsal surface of the largest hermaphrodite. 



Integument. 



The integument consists af 4 hu'ers i) cuticulum, 2) epidermis. 3': cutis. 4) integumental muscular la)'er; it is the de- 

 velopment of the two last named layers that, especially, varies in the different species, and appears usually to increase with 

 the thickness of the bod)', i) The cuticulum is thin') and apparently structureless. It, however, consists of two la)'ers ; one outer 

 pellucid, extremely thin, non-staining la)'er, and an inner thicker usualh' deep-staining one. The outer la)'er appears to be 

 leebly striated. The cuticle is, more or less, adherent to the subjacent epithelial cells trom which it is secreted, I have 

 not detected any distinct openings or pores, 2) The epidenuic cells \'ar)', somewhat, in tlirm and \'olume in the 



^) In M, gigas its thickness is about 0.0035 mn^- 



