Aiixf ndlaii, HydroiJu. To 



Zool. Jiihil)., Suppl. vi., 19()o. p. aGO. :)5:5. 5G2, ti-s. 

 K, L. Want'ii. Ann. Nat. Govt. .\Ius.. i.. IDOS. p. :!:'„•<. 

 f. 1!). 

 ('aiitlKiiti(l(iri(i hrcvisci/pJtift, Sars, Middelliavet's Lit. Fanna, 



1857, p. locS, pi. i., tigs. 12-i:i. 

 L(t()i>H'(iea caliciilafa, Alhnan, Ann. Mag. Nat. Hist. (•)), 



xiii., 186-t, i>. .-{T.-',. 

 Ci;/ti(i {OrfJiopi/.rix) poicr'nnn, Agas.siz. Coiitr. Nat. Hist. 

 r.8., iv.. 1.SG2. p. 2!)7, pi. xxviii.. tigs. 1-20, pi. xxix., 

 tigs. 1-5. 

 Orfliopiii'iA pottrimii, A. Agassiz. Catal. N. Amer. .\cal.. 



1865, p. 81. 

 Catnpa?iular/a poieriiim. Nutting, U.S. Fisli. Comni. Hull. 



for 1899, 1901, p. .'Ui, tig. 24. 

 Clytia caliculafn. Nutting, Proc. Wash. Acad. Sui., iii.. IDOl. 



p. 170, pi. xvii., fig. 1-2. 

 Eucopdla calicidata, Fraser, Bull. Labor. N. H. State Univ. 



Iowa, vi., 1911, p. .3G. 



Campanularia luttyra, in part, Levinsen, Vid. Meddel. fia 



den naturh. Foren, 1892, p. 26. Marktanner-Turnerets- 



cher, Zool. Jahrb., viii., 1895, ■^. 406. Birula, Ann. 



Mus. Zool. Acad. Sc. St. Petersbourg. 1898, p. M-6, 



fig. 1-3. Billard, Arch, de Zool, exp. et gen. (4). vii.. 



1907, p. 340. Jaderholm, Kungl. Svensk. Vetenskaps- 



akad. Handling., Bd. 45, 1909. p. 65. Broch, Fauna 



arctica, v., 1909, p. 185, 225. Linko, Fauna de la 



Russie, i., 1911, p. 170. 



(Not Campanularia calicvlata. Calkins, Pioc. Boston Sou. 



Nat. Hist., xxviii.. 1899, p. 351. pi. ii., fig. 11-lle.. 



pi. vi., fig. lid.) 



This cosmopolitan species has been often described, l)ut all the 



older descriptions missed an ijnportant point in the structure of 



the hydrotheca, namely the bilateral development of the lower poi- 



tion, Avhich is distinctly compressed, so that the hydrothecae at this 



pai't may be said to have two broader and two narrower sides. 



I have generally found the perisarc of the nariower sides somewliat 



thicker than elsewhere, so that on viewing the hydrotheca in its 



broader aspect the wall appears thicker than when seen in the other 



direction. In a typical hydrotheca, as seen in its narrow aspect. 



tlie two sides appear as convergent lines, straight throughout, the 



outline in this aspect })eing therefore distinctly funnel-shaped. But 



