1865. 

 1867. 



Mysta barbi 



1871. 



>} >> 



1874. 



•>■> >) 



1879. 



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1879. 



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1883. 



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1901. 



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MYSTIDES. 109 



Synonyms. 



Mysta barbata, Malmgren. Nord. Hafs- Annul., p. 101, Tab. xv, f. 34. 

 idem. Annul. Polych., p. 26. 



Ehlers. Sitz. Phys. Med. Soc. Erlangen, III, p. 79. 

 Malm. Op. cit. Groteb., p. 81. 

 Tauber. Annul. Danic, p. 89. 

 Theel. K. Vet. Akad. Handl., Bd. xvi, 3, p. 34. 

 Wiren. Chgetop. f Vega' Bxped., p. 400. 

 Mcintosh. Ann. Nat. Hist., ser. 7, vol. viii, p. 223. 



Habitat. — Procured in the trawl a little east of the island of May, January, 1891. 



Spitzbergen (Ehlers) ; Nova Zembla (Theel) ; Norway (Canon Norman) ; Siberia and 

 Behrings Strait (Wiren). 



Head (Plate LVIII, fig. 10) in the preparation bluntly conical, with two conspicuous 

 eyes posteriorly. At the truncated apex are two short subulate tentacles on each side. 

 The tentacular cirri are two in number on each side, viz. a dorsal and a ventral, the 

 former more than twice the length of the latter, somewhat thick at the base, but 

 tapering to a fine point. 



Body slightly diminished towards the head and more distinctly tapered posteriorly, 

 somewhat rounded on the dorsum, flattened on the ventral surface, and probably 

 terminated by two cirri posteriorly. A brownish band passes from the head backward 

 on each side within the line of the lamellaa, and a median stripe of similar hue occupies 

 the ridge of the body. 



The foot (Plate LXIX, fig. 10) seems to correspond with Malmgren's description and 

 figure, though it must be mentioned that there is considerable difficulty in following the 

 distinctions of the various species given by the author. The somewhat imbricate dorsal 

 cirrus may be described as sub-orbicular, having a longer transverse diameter in the 

 anterior feet and a longer obliquely vertical diameter in the posterior feet, with a 

 tendency to a point externally, where it goes much beyond the setigerous process. The 

 latter is somewhat small, bifid, and bears the bristles (Plate LXXVII, fig. 19), which 

 present a shoulder, from which a denticulated ridge passes to a large curved spine, with 

 a smaller spine opposite it, the blade of the terminal process being between them. It 

 (terminal process) is wide beneath and tapers to a fine point, and the edge is serrated. 



The ventral cirrus is proportionately broad anteriorly, narrower and more pointed 

 posteriorly, and it projects considerably beyond the setigerous lobe. Malmgren describes 

 its form as ovate, with a rounded apex. In this form it was rather ovato-lanceolate. 



Reproduction. — The specimen is a female laden with minute ova — apparently free in 

 the coelomic space, so that the breeding season would appear to be in spring (May). 



Genus XXXVIII.— Mystides, Theel, 1879 (char, emend.). 



Tentacles, four long, or short, lateral rather than terminal ; tentacular cirri, three 

 on each side, viz., on the first, second, and third segments ; eyes, two, large. The British 



