ARCTIC SEA TO THE WEST OF GREENLAND. 5 



with those of C. frondosa, they are by themselves quite insufficient for comparative 

 determination ; whilst, on the other hand, it is definitely stated that the calcareous sup- 

 ports, though few, " are in the form of slender, perforated, crested spicula, similar to 

 those found in Thyone and Thyonidium " (1. c. p. 53). Such crested spicules certainly 

 do not occur in any specimens of C. frondosa from the North-European seas ; whilst 

 from the fact that they are specially noted by Mr. Ayres (and it is a feature much 

 more readily passed over than not) we are inclined to regard Bothryodactyla grandis, if 

 not an independent species, certainly with but little doubt as a well-marked variety. 

 In further support of this opinion it may be noted that Sars examined specimens of the 

 American C. frondosa both from Massachusetts and Fundy Bay, and specially asserts 

 their identity with the European type. 



Distribution. 



a. Greenland : Godhavn, lat. 69 14' N. (Stimpson, Ltitken, ' Valorous' Exped.). 



b. North of American Continent: Assistance Bay, about lat. 74 N. (Penny's 

 Exped.}, the most northern locality on record ; Labrador ( Verrill) ; St. George's Bank, 

 30 fms. (Verrill); Grand Manan, low water, stony bottom (Stimpson); Massachusetts 

 (Gould); Eastport, 20 fms., stony bottom (Verrill); Gulf of Georgia (Selenka); 

 ^ Florida Reef, 118 fms. (Pourtales) ; San Francisco (Ayres). 



c. North of European Continent : Spitzbergen (LutJcen); Scandinavian coasts, Ice- 

 land, Faeroe Islands, Shetlands, British Islands. 



Description of the Illustrations of this Species on Plate I. 



Fig. 1. A medium-sized specimen: natural size. 



2. A young specimen of the same species : natural size. 



CUCUMAKIA CALCIGEKA (Stimp.), Selenka. Plate I, Figs. 3-8. 



1851. Pentacta calcigera, Stimpson, Proceed. Boston Soc. Nat. Hist. vol. iv. p. 67. 



1852. ? Cucumaria Hyndmanni, Forbes, Sutherland's Journal of a Voyage &c. vol. ii. Append, p. ccxiv. 

 1857. Cucumaria Korenii, Liitken, Vid. Heddel. N. Forening i Kjobenhavn, 1857, p. 4. 



1866. Pentacta calcigera, Verrill, Proc. Boston Soc. Nat. Hist. vol. x. p. 352. 



1867. Cucumaria Korenii, Selenka, Zeitsch. f. wiss. Zool. Bd. xvii. p. 350. 



1867. Cucumaria calcigera, Selenka, Zeitsch. f. wiss. Zool. Bd. xvii. p. 351. 



1868. Cucumaria calcigera, Semper, Ecisen im Archipel der Philippinen, Holothurien, p. 53. 

 1868. Cucumaria Hyndmanni, Semper (pars), ibid. p. 269. 



Body elongate and cylindrical, the posterior third tapering gradually to a fine 

 extremity ; anterior end more rounded, and the median thickness of the body main- 

 tained till very much nearer the oral region. The body is generally more or less curved 

 to one side, sometimes through more than half a circle, which gives to this species a 

 crescent- or even horseshoe-shaped contour. The ambulacral feet are arranged in single 

 pairs, and form five narrow, equally-developed bands. The suckers are placed very 

 closely together ; consequently the number extending from tip to tip is proportionally 

 great, whilst sometimes, in the middle part of a band, the pairs become reduplicated by 



