78 AMERICAN HYDROIDS. 



Distal part of hydrothecse neither expanded nor contracted. 



More than two-thirds of adcauline wall adnate ............................................. mttneana. 



Less than one-half adcauline wall adnate. 



Adnateness varying greatly, hydrothec;L> large ...... . ................................ magellanica. 



Adnateness fairly constant. 

 Hydrothecse very small. 



Stem geniculate, gonangia deeply ani.ulated ..................................... minnln. 



Stem flexuose, gonangia feebly anmilated ...................................... li'i-iiixrin. 



Hydrothecse niedium or large. 



Margins extensively reduplicated .............................................. ili-nlijn-n. 



Margins not extensively reduplicated. 



Gonangia deeply annulated throughout ____ ......................... ____ tririmiiiiliitii. 



Proximal part of gonangia smooth ................................ . ......... trujiifu. 



Hydrothecie with two teeth. 



Hydrothec;e inclined forward ................ . ............................................... - ...... rlitrkii. 



Hydrothecie projecting outward ............. ; .................................................... ejiiscojitix. 



Hydrothecse immense, teeth inconspicuous ................................................ . ......... HHII/H". 



Hydrothecal margin smooth. 



Hydrothecie perfectly cylindrical ............................................... . ......... - ...... .formuxit. 



Hydrotherae the shape of the frustum of a cone .................................................... luirtluiili. 



Hydrothec;e with beveled margins ............................... . ................................... nana. 



/ 



SERTULARELLA GAYI (Lamouroux). 

 (Plate XIV, figs. 1-7.) 



Sertiilarin. gmji LAMOUROUX, Exposition Methodique, 1S21, p. 12. 

 La Scrliilnrin <li- (imj DE BLAINVILLE, Manual d'Actinologie, 1834, p. 481. 

 Si'rliiliii-in i/ni/i LAMARCK, Hist. nat. anim. sans Vert., 1836, p. 152. 

 Sertularia potyzonias VO.T. ft, JOHN.STON, Brit. Hyd. Zooph., 1847, p. 62. 

 K-rtuliii'iii i/'ii/i HINCKS, Ann. and Mag., 3d ser., VIII, 18(31, p. 252. 

 Sertuliirin ;/"</' ALDER, Trans. Tyneside Field (.'lab, V, 1862, p. 2:i7. 

 Serlularelln ;/".'/' HINCKS, British Hydroid Zoophytes, ISHS, p. 237. 



t i/ni/i SAKS, P.idrag til Kundskaben om Norges Hydroider, 1873, p. 21 



i'l/d ijni/i var. rnlmxln Ai. I.MAN, Pnrcupiiie Expedition, 1874, ji. 471. 

 f-li'iiiil'in'Hit i/ni/i XOKMAX, Ann. and Mag., 4th scr., XV, 1M75, p. 173. 

 Sertularellagayi, var. robusta ALLMAN, ilem. Mus. Comp. Zool., V, No. 2, 1S77, p. 22 

 Scrlnliiivllii. ijmji '! VKHRILI,, Check List, 1870, p. 18. 



Sertiiliiirl/ii. i/ut/i WINTHER, Fortignelse di i Danmark Hydroider, 1880, j>. 27(i. 

 \,,7/<//v// i/ni/i. FEWKES, Bull. Mus. Comp. Zool., VIII, No. 7, J881, p. 128. 

 ,V, rtuliiri /In i/ni/i KlRCHENPAUER, Nordischc (Tattungen, 1S84, p. 41. 

 K-1-liilnirlln i/ni/i SEIIEKSTEDT, Bihang till K. Svcuska Vi-t.-Akad., 18SSI, p. IB 



i .'/".'/' Bol'KNE, Hydroids uf Plymouth, 1890, p. IKHi. 

 -l/ii ;/<<//<< iAiisTANG, Journ. Marine Biol. Assnc., Ill, 1895, p. 224. 



-i-ll<i ijni/i CiiAWKuKii, Ann. and Mag., 6th ser., XVI, 1895, p. 261. 



-i'llii i/ni/i NUTTIXC,, Bahama Expedition, 1895, p. 88. 



rlhi ,/ni/i DUERDEN,- Proc. Koy. Dublin Sue., X. S., VIII, 1897, p. 416. 



-fllii i/'i'/i A 1. 1, EN, Journ. Marine 15iol. Assoc., 1899, p. 452. 



-i-llii i/ni/i I'.IINNEVIK, Norwegian North Atl. Exped., 1899, p. 76. 



lhi i/nii! llAirn.Arii, Revision Sertularella-Arten, 1900, ji. 61. 

 Rertiiluri'llii i/ni/i NUTTING, Ilyilroids of W ..... Is Hole Region, 1901, p. 36:;. 

 Sertularella ;/ni/! HAROITT, American Naturalist, 1901, p. 391. 



i, . Colony .straggling in habit, attaining a height of about (! inches in sonic cases. 

 Stem fascicled, made up of a number of intertwining and intimately connected tubes, which in 

 the aggregate form a very thick woody stem that bears no trace of internodes or regularity of 

 branching. Branches given off irregularly from the stem, but with a tendency toward a pinnate 

 arrangement. Sometimes a large, branch is given off from the main stem which resembles the 

 latter in all particulars, otherwise the brunches are nonfascicled, sinuous, divided by oblique 

 nodes into regular internodes, each of which bears a hydrotheca. Hydrothecse ovate, with the 

 distal ends narrowed and bent slightly outward, adcauline side more or less marked by trans- 

 verse rugosities, distal two-thirds free, ending in a margin ornamented with four shallow equi- 

 distant teeth and an operculum consisting of four valves. 



