OF THE NORTH-POLAR EXPEDITION- 235 



Myriozoum coarctation et subgracile, Hincks, I. c. p. 106; Smitt, I. c. 

 pp. 18 & 119. 



Millepora truncata, Fabricius, Faun. Grcenl. p. 432 ; Packard, I. c. 

 (teste Smitt). 



? Myriozoum subgracile, D'Orb. Pal. Franc, p. 662. 



Millepora truncata (pars), Lamouroux ; Pallas. 



Hab. (Forma subgracile). Franklin- Pierce Bay, Smith's Sound, 

 13-15 fms. (H. W. F.) ; Arctic Sea (Sir Ed. Belcher's Expedi- 

 tion^.)) South Labrador (Packard) ; Newfoundland (D'Orbig.) ; 

 Spitzbergen, 19-80 fms. (Smitt) ; Greenland (Moller $f Torell) ; 

 Holsteinborg Harbour, entrance of Baffin's Bay, 175 fms. (Nor- 

 man, 'Valorous' Dredgings) ; Ireland, 100 fms. (Wallich, teste 

 Hinclcs). (Forma coarctata) Norway (Strom, Sars, Sfc.) ; Finmark 

 (Loven, Sars). 



That two apparently distinct forms of Myriozoum are found 

 in the northern aud Arctic seas admits of no doubt. The 

 Leieschara coarctata of Sars, with a large avicularium above the 

 mouth of almost every zoceeium, appears at first sight to be quite 

 distinct from a slenderer form in which, as is often the case, 

 there are no avicularia to be seen, or, in other cases, they are rarely 

 and irregularly scattered amongst the mouths of the zooeeia, are 

 of far smaller size, and arise, as it would seem, in the transfor- 

 mation of one of the pits or alveoli with which the surface of the 

 zoarium is covered. Or, again, avicularia may be seen in the 

 same situation as in the typical M. coarctatum, but of small size 

 and very few in number. Upon the survey of numerous speci- 

 mens from different localities, it seems to me that a transition 

 can be traced between the typical form and that termed by 

 Prof. Smitt M. subgracile, which, as he assumes, is in all 

 probability identical with M. subgracile of D'Orbigny, from 

 Newfoundland. 



The few r specimens, probably belonging to not more than one 

 or two individual growths, collected by Captain Feilden are of 

 the subgracile type, which would appear in all cases to be the more 

 northern form. 



It may be mentioned that there is a still slenderer, quite 

 unarmed species in North Japan, in which the zoarium is not 

 constricted, probably closely allied to the above. 



Genus Eschara. 

 1. Eschara elegantula, JJOrb. 



Eschara elegantula, D'Orbigny (1851), Pal. Franc, p. 102; Smitt, I.e. 

 LINN. JOURN. — ZOOLOGY, VOL. XV. 18 



