90 AMERICAN HYDROIDS. 



campanularian And sertularian types, agreeing with the former in the fact that the hydrothecse 

 arc radially symmetrical and pediculate and with the latter in the structure of the hydrothecse 

 and operculum. Were it not for the presence of the hydranths this form could readily be mis- 

 . taken for the, gonangia of <S'. fusiform ix, although the hydrothecse are more slender than any 

 representation of the gonangia of S. fusiformis that I have seen. It is, of course, possible that 

 older specimens will demonstrate that the adult colony resembles that of S. fusiform is in the 

 manner of branching, but the hydrotheca? are readily distinguished. 

 TI/JH xlidc. Cat. No. 18717, Museum of State University of Iowa. 



SERTULARELLA PICTA (Meyen). 

 (Plate XX, figs. 5-7.) 



H,-i-tit/iir!ti jiiiin MEYEN, Uber Lcuchten des Meeres, 1834, p. 201. 

 \rtuliii-i-llii jiirln HAKTLATH, Revision dcr Scrtnlarella-Arten, 1900, p. 77. 



TrvjilioKtimi: Colon} 7 growing in dense masses and attaining a height of 6 to 8 inches. 

 Branches alternate, divided into regular internodes each bearing a hydrotheca and divided by 

 one or two annular constrictions. Hydrothecse alternate and axillary. Margin witli four small 

 teeth and a small opening, owing to an internal thickening of the perisarc near the margin. 



Go/ioKomi. (lonangia alternating with the hydrotheca?, evenly annulated throughout and 

 with four marginal teeth. 



DistriliutiiDi. On the East Coast of Terra del Fuego and near the Falkland Islands (Meyen); 

 Puerto Toro and Lennox Island (Hartlaub). 



Hartlaub, who has examined the type, says that Meyen is in error in saying that the gonangia 

 alternate with the hydrotheca?, and that the presence of the hydrotheeal teeth is uncertain. 

 Hartlaub and Kirchenpauer both suggest the identity of this species and S, tj<imliclt<(ilii 

 Lamouroux. 1 



TI//IC. In the Berlin Museum. 



SERTULARELLA MEGASTOMA, new species. 

 (Plate XX, figs. S-9.) 



Trophosome. Colony rigid, compact, pinnate, the single fragmentary specimen known 

 attaining a height of about ~2 inches. Stem fascicled, straight, without evident internodes, color 

 dark brown. Branches regularly alternate, rigid, without evident constrictions at base and 

 without evident internodes. Hydrothecse cylindrical or subconoid, outer profile nearly straight, 

 without evident swelling at base, distal two-thirds of adcauline wall free. No noticeable 

 constriction near distal end, margin square with four low but evident teeth. Operculum of four 

 valves. 



tj/HioKinne. Gonangia borne on branches, small, oblong-ovoid, regularly and deeply 

 annulated, with a very large quadrate aperture, and without an evident neck. 



Di*tril>ut;.All><i1r<>xx Station -2353, lat. N. 2() r.!i'. long. W. 86 23', 167 fathoms. 



This very distinct species has a particularly rigid habit of growth, without the sinuous 

 I icnds to its stem and branches almost universally found in the genus. The small gonangia are 

 unique in the genus, so far as I know, in the very large size of the quadrate aperture. 



TIJJI, 'x/t'th-x. Cat. Nos. 19765, 19766, U.S.N.M. Cat. No. 18708, Museum State University 

 of Iowa; also in collection of the author. 



SERTULARELLA POLYZONIAS (Linnaeus). 

 (Plate XXI, figs. 1-2.) 



t.'i-i'nl Tunlli CnriiUine ELLIS, Essay Nat. Hist, Corallines, 175. r >, p. 5. 

 Si'iiii/iii-i/i iiii/ii:,,itiux LINN r.i s, Systcina Xatunr, I7">S. p. SI". 

 Sertvlariajlexuosa LINN.KI'S, Systcina Natunr, 17~>s, p. S14. 

 Si-rtiili<ri<t piily-miiiHs LINN.EUS, Fauna Suecica, 1761, p. 541. 

 ,v. 'i-lii/iii-in jlf.fiinsii LIXN.V.CS, Fauna Snecii-a, 17H1, p. 542. 



'See Hartlauli, K.-vision der Sertularella-Arten, I'.MMI, p. 77.:m.l Kiivli,.ni>auer, Nordische Gattungen und Arten, 

 1884, p. 38. 



