THE PLUMULARIDJE. 69 



KEY T<> A.MEKK'AN Sl'ECIES OF ANTENXULARIA. 



Intermediate interuodea present, interuodes without internal thicken- 

 ings, proximate hydrothecse divided from stem by two nodes 



mi lennhia. 



Hydroeladia strictly verticillate Proximate' hydrotheca not divided from stem by nodes nmericaiia. 



Less than six hydrocladia to each verticil. Intermediate internodes 

 niiruially absent ainiph'j'. 



Hydrocladial internodes with distinct internal thickenings nujosa. 



Hydroeladia borne on very long stout processes from stem. Color of 



Hydroeladia not strictly verticillate. 



L'olouy, brown genivulata. 



Hydroeladia borne on processes of moderate si/e. Color of colony, yel- 

 low pinnata. 



The arrangement of internodes in the American specimens is utterly unreliable, as the char 

 acteristic features of both A. nntennina and A.ramonuis often, indeed usually, found on the same 

 hydrocladium, the proximal portion being- made up of alternate hydrothecate and intermediate 

 iuternodes. 



ANTENNULARIA ANTENNINA (Linnzus). 

 (Plate IX, tigs. 1, 2.) 



Sertularia aiitentiiim LINN.EUS, Systema Natura', 1788, p. 1310. 



Serlulariii aitteiiiiiiiti PALLAS, Eleuchus Xoophytorum, 1766, p. 14li. 



Xemertesia aiileiinimi LAMOUROUX, Hist, des Polyp, coral, flex., 1816, p. 1G3. 



AntrHuiilai-iii intliriiKi LAMARCK, Anim. sans Vert., 1836, 2d ed., II, p. 156. 



Anteiiiiuluriu iiiili'iiiiina JOHNSTON, Brit. Zooph., 1847, 2d ed., p. 86. 



Antciinulnria anti-niiina HIXCKS, Brit. Hydroid Zooph., 1868, p. 280. 



XemertfHiii anleiiuiua KiKriiEXi-.U'ER, Ueber die Hydroidenfam. Plunmlaridir, 1876, Pt. 2, p. 51. 



Autennularia antennina MARKTANNEK-TuRNERETSCHEK, Die Hydroideu des k. k. naturhis., Hoi'mus., 1890, p. 260. 



Trophosome. Colony growing- in dense clusters of upright stems, attaining a height of 8 to 10 

 inches, uiibranched or very sparsely branched; stem with the cienosarc canaliculated, divided 

 into obscure interuodes, each of which bears a verticil of hydrocladia on processes from its distal 

 end, there being usually more than six hydrocladia to each verticil; hydrocladia divided into 

 alternating hydrothecate and intermediate iuternodes, the former being the longer. Hydrotheca; 

 small, cup-shaped, with slightly everted margins; supracalyciue ueinatophores present; a mesial 

 nematophore at the base of each hydrotheca, one and sometimes two to each intermediate 

 iuternode, and two in the axil of each hydrocladium. 



Gonosome. Gonangia ovate, with a subterminal aperture, borne singly in the axils of the 

 hydrocladia. 



Distribution. Shores of Europe and Great Britain (Hincks) ; Newport, Rhode Island (Verrill) ; 

 Albatross Station 20UG, lat. 1ST. 42 20', long. W. 05 50'; depth, C5 fathoms; Albatross Station 

 2302, lat, N. 35 U', long. W. 75 03'; depth, 71 fathoms. 



ANTENNULARIA AMERICANA, new species. 

 (Plate IX, figs. 3, 4.) 



Trophosome. Colony uubranched or sparsely branched, attaining a height of 9 inches. 

 Co?nosarc extensively canaliculated; hydrocladia arranged in distinct verticils of usually more 

 than six, each borne on a very long process from the stem, irlrich is not separated from the /iro.rimal 

 hydrotheca by more than one node; proximal portion of each hydrocladium made up of hydro- 

 tliccate internodes only, distal portion usually showing intermediate internodes; all hydrocladial 

 interuodes more slender than in A. antenmtw. Hydrotheca' small, cup-shaped, witli margins some- 

 times slightly everted, borne below the middle of the iuteruode.s; a pair of large supracalyciue 

 nematophores borne on small processes below the postero-lateral margin of each hydrotheca; a 

 mesial nematophore below each hydrotheca, and one or two on each intermediate iuternode or 

 above each hydrotheca where the intermediate internodes are absent; two or three cauline uema- 

 tophores in the axil of each hydrocladium, and the others scattered somewhat irregularly over 

 the stem. 



