GLYCERA EHLERSI. 481 



Habits. — This species frequents sandy gravel and mud (Shetland). Dr. Johnston 

 found his under stones and buried in gravel or sand, not far below the surface, and, as 

 mentioned, it sometimes occurs between tide-marks in fissures of sandstone. 



In the epitocous form (G. setosa) the body becomes more elongate and attenuate and 

 the feet are more prominent and longer — with attenuate bristles — which with the foot 

 give a character to the form. Two specimens procured in the 'Valorous' were males. 

 In these both spines and bristles become greatly elongated, but the latter retain their 

 essential structure. The example from eight fathoms in Bressay Sound seemed also to 

 be a male. It was much smaller than the foreofoine. 



This would appear to be the species referred to by 0. F. Muller (1788) as Nereis alba, 

 judging from his description and figures. 



Malmgren (1867) included under G. capitata both the northern type of CErsted and 

 the southern G. lapidum, making its sexual form, G. setosa, a separate species. 



Ehlers (1868) showed that (Ersted's Glycera setosa, and Johnston's G. alba, as well as 

 the G. lapidum and G. Mulleri of De Quatrefages, all pertained to this species. 



In Verrill's Check List for the U.S. Commission (1879) Rhynchobolus albus, capitatus, 

 and dibra?ichiatus appear. 



2. Gtlycera Ehlerst, Arwidsson, 1898. Plate LXXXVI, figs. 4, 4', and 4 a— bristles ; 



Plate LXXXVII, fig. (>— foot. 



Specific Characters. — Head very long, attenuate, of more than twenty rings, muscles 

 separated by a median streak. Body elongated for a Glycera, segments two-ringed; 

 dorsal surface rounded and marked by a slight median groove. The ventral surface has 

 a median ridge flanked by a groove at each side. Proboscis with rather long digit-like 

 papillge 1 slightly tapered towards the tip. Jaws with a powerful curved main fang having 

 a broad base with two long spurs. Foot has the dorsal cirrus unusually large, two long 

 papilla? or lobes close to each other and almost parallel anteriorly, and a single flattened 

 lobe with a rounded edge posteriorly. Ventral cirrus short and conical, its tip nearly 

 in a line with the edge of the posterior lobe. 



Synonyms. 



1868. Glycera lapidum, Elders. Borstenw., ii, p. 652. 



1898. „ Ehlersii, Arwidsson. Bergens Mus. Aarb., No. xi, p. 19. 



1905. „ „ Mcintosh. Ann. Nat. Hist., ser. 1, vol. xv ; p. 41. 



Habitat. — Eighty fathoms, St. Magnus Bay, 1867. Nine miles off Balta, fifty to 

 sixty fathoms, 1868 (Dr. J. Gr. Jeffreys). Fifty-three fathoms, Station III, ' Knight Errant/ 

 3rd and 4th August, 1880. 



Shores of France (St. Malo). 



1 Grube describes them as short and leaf-like. He apparently thinks this like G. capitata, but 

 with the anterior lobes of the foot longer, and the segments two-ringed. 



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