66 AMERICAN HYDROIDS. 



THUIARIA IMMERSA, new species. 



(Plate IX, figs. 3-4.) 



Tliiiinrid loni'liilia MARKTAXNER-TURXERETSCHER, Hydroiden des k. k. naturhist. Hofmnseums, 1890, p. 236. 

 Tlniiiiria 1 one-hit in MAfiKTAXXER-TrRNERETSCHER, Hydroiden Ost Spitzbergen, 1895, p. 422. 



TrojilinxiniK . Colony (incomplete) less than 1 inch high. Stein irregularly liut deeply 

 annulated throughout the thick proximal portion which bears no branches and which appears to 

 have been broken oft' and renewed, the new portion bearing all the branches. Distal part of stem 

 feebly geniculate, without evident nodes, bearing alternate lateral branches, one to each genicn- 

 lation, and two rows of hydrothecse. Hydrothecse alternate, slender, flask-shaped, much smaller 

 distally, the apertures opening vertically and not projecting at all from the general surface of 

 the hydrocaulus. Just under the lower edge of the margin is a thickening of the hydrothecal 

 wall that is plainly evident in a side view. The aperture is perfectly smooth and round, without 

 teeth. There is a well-marked space between the top of one hydrotheca and the bottom of the 

 next. Texture of colony corneous, much stifl'er and stronger than in T. lone-hills. 



Gonoxo/ne. Not known. 



D!xti-!liiit!<ii). Coast of Greenland, U. S. S. Alert, 188-i; Austro-Hungarian Polar Expedition, 

 lat, N. 7fi 14', long. . 85 5-i'. (Marktanner-Turneretscher.) 



This species seems to me to be certainly distinct from T. lonchitix of authors, which is a much 

 larger and more graceful species, with hydrothecie projecting perceptibly from the stem and 

 branches, and opening obliquely upward and outward. The specimen collected by the U. S. S. 

 Alert agrees exactly with the figure and description given by Marktanner-Turneretscher under 

 the name Tlininrin lix'/iit!x. 



He calls attention to the main differences between this specimen and the typical loin-Jil-tix. 

 but apparently did not regard these differences of sufficient import to warrant a separation, an 

 opinion with which I am unable to agree. 



It is possible that other writers have had this species in hand and described it either as 

 T. niiii'iiliitii or T. loni'hiflx. 



Type. In the U. S. National Museum. Fragment in collection of the author. 



THUIARIA LONCHITIS (Ellis and Solander). 

 (Plate IX, figs. 5-8.) 



Rea-Splmiinirt r I'nlt/podi/ ELLIS, Essay Nat. Hist. Corallines, 1755, p. 42. 



Hn-liiltiriii Innrliilia Ei. us and SOLANDER, Nat. Hist. Zoophytes, 1786, p. 42. 



Sertulana l,,,,i-liil is r.osc, Hist. Nat. des Vrrs, 1802, p. 101. 



Si'rtiiliirin lii-lii'iinxlrtiiii THRTON, British Fauna, 1S07, p. 21(1. 



.' Xii/i'llnxli-niii I Xfi'lii/ui-id ) di-lifii/dln ( >K KN, I.c'hrbnch der Naturgesdiichte, 1815, p. 93. 



Cettar'xi Inn.cliitix LAMAHCK, Hist. Nat. Aniin. sans Vert., ISlli, p. 139. 



Tliiiinriii iniii-nlnln FLEMING, British Animals, 1S2S, p. 5|."i. 



Tliniiiriii- ni'lii-nlntn HASSALL, Ann. and Mag., VII, 1841, p. 2S4. 



Tliuidi-iii diilriildid HVNDMAX, Ann. and Mag., X, 1842, p. 20. 



Tlmidi-id diiii-n/dld (iu.\y, Brit. Animals, 1847, p. 70. 



Tliiiinriii (irl/nilitlii .TOIINSTOX, Hist. Brit. Zooph., 1847, ]i. 84. 



.' Thiiidi'in tirtiruliitit ALDER, Cat. Zooph. Northnmb., 1857, p. 27. 



fThniiiriii iirtii'iildlii HIXCKS, British Hydroid Zoophytes, 18H8, p. 277. 



Tliiiidi-in. iiiiirulatn WIIITKAVES, Ann. and Mag., 4th scr., X, 1873, p. 345. 



Tliiiinriii iirliculalii Scni'LZE, Nonlsce Exiicd., 1874, p. !.'!.">. 



fTlntidrid di-lirii/iiln MIORKM IIKIIWSKY, Ann. and Mag., 5th per., I, 1878, p. 324. 



Tlniidi-i/i diiii-nldlii VERRILL, Prelim. Check-list, 1879, p. 18. 



.' Tliuinrifi nrtirnliilii D' URBAN, Zooi. Barent's Sea, 1880, p. 269. 



Thnic.riii loiirliitix KiKciiExr.M'ER, Nordische Gattnngen und Arten, 1884, p. 22. 



? Tliuiaria artictilata BERGH, Goplepolyper f ra Kara Ilavct, 1887, p. 337. 



Tlniinrin iirlirnliitii BOFKNK, Ilydr. . ids of Plymouth, 1889-90, p. 397. 



Tlnijiirid ImichitixLEViasKS, Vid. Uclb. "Hauchs" Togter, 1893, p. 371. 



Tlniidi-id articulata CRAWFORD, Ann. and Man., 6th ser., XVI, 1895, p. 261. 



: ; Tliiiinriii iirtii-iiliitii BOXXEVIE, North Atlantic Expedition, 18VI9, p. s:;. 



Tliiiliirin ni'liriilnln I'icTETand BEDOT, Hydraircs de 1'Hirondelle, 1900, p. 25. 



Tliiiinriii. (ti'tiriildtd \VniTEAVKs, Cat. Marine Invert. Eastern Canada, 1901, p. 27. 



Tli]iirid Inni-liiiis S.EMUNDSSOX, Bidrag til Kundskaben islandake Hydroider, 1902, p. 65. 



