108 AMERICAN HYDROIDS. 



i CRAWFORD, Ann. and Mag., 6th ser., XVI, 1895, p. 261. 

 Dynuinfnn rosacea BONNEVIE, Norwegian North Atlantic Exped., 1899, p. 79. 

 ia rosacea NUTTING, Hydroids of the Woods Hole Region, 1901, p. 361. 



HARGITT, Amer. Naturalist, 1901, p. 392. 

 Diphasia rosacea WOITEAVES, Marine Invert. Eastern Canada, 1901, p. 26. 

 Diphasia rosacea S.EMUNDSSON, Islandske Hydroider, 1902, p. 66. 



Tniphoxome. Colony attaining a height of 3 or 4 inches, of very delicate texture, trans- 

 lucent. Stem not fascicled, its proximal portion smooth and without hydrothecffl, no regular 

 internodes; remainder divided into regular short internodes, each bearing a pair of opposite 

 hydrotheca* and sometimes a branch. Branches alternate, distant, often irregularly spaced, 

 proximal internode without hydrothecse, others bearing a pair of opposite hydro thecse; branches 

 themselves often divided into branchlets. Hydrothecse strictly opposite, long, tubular, the two 

 of a pair not contingent in front but with their proximal adcauline sides parallel, upper one-third 

 to one-half free and bending abruptly outward and forward and ending in an oblique margin, 

 which is sinuous but not toothed. Operculum of a single adcauline flap, usually situated just at 

 the margin, but when closed sinking considerably below the margin, especially on the adcauline 

 side. Nodes of the branches just between the distal divaricated portions of the hydrothecse. 



Gonosome. Gonangia borne in rows on the upper sides of branches, male gonangia long, 

 slender, narrowing very gradually proximally to a short curved pedicel and very abruptly 

 distally to a small tubular neck and minute round aperture; sides ornamented with eight com- 

 pressed longitudinal ridges ending in points on distal end of gonangia. Four to eight spermaries 

 are seen in a row through the transparent gonangial walls. Female gonangia larger, more robust, 

 pyriform, with eight conspicuous longitudinal ridges ending in lamellate processes which curve 

 inward toward a common center, and two of which, on opposite sides, are much larger than the 

 other six; apparently an internal marsupial chamber of globular form can be seen in mature 

 gonangia. 1 When immature the gonangia are obconical in form, with eight regularly spaced 

 projections around the top. 



D!stril)ut!<m. New England coast, common (Verrill); Labrador (Packard); Gulf of St. 

 Lawrence (Whiteaves); British coasts (Hincks); Denmark (Winther); Norway (Levinsen); Iceland 

 (Samiundsson); North Sea (Schulze). 



Albatrox* Station 2250, lat. N. -0 17' 15", long. W. 69 51' 45", 47 fathoms. 



This is a well-known shallow water species, occurring from tide level to about 50 fathoms. 



DIPHASIA TAMARISCA (Linnaeus). 



(Plate XXVIII, ligs. 6-7.) 



Sen tamarisk ELLIS, Nat. Hist. Corallines, 1755, p. 4. 

 Sertuliii-in liiniiirigcti, LiNN.Ers, Systema Natune, 1758, p. 808. 

 Kn-tiiliiriii I'l/iini-ixrii HOUTTUYN, Natuurlyke Historic, XVII, 1761-1773, p. 533. 

 Serlulitria tttmarixrn PALLAS, Elenchus Zoophytorum, 1766, p. 129. 

 i Iniiinrixi-ii LINN.EUS, Systema Natune, 1767, p. 1307. 

 i Inniiirixra BOBDAERT, Lyst der Plant-Dieren, 1768, p. 160. 

 (Si rlnlnriiL tmnnrixrux MARATTI, De Plantis Xnophytis, 1776, p. 26. 



Tiiiiiiirixru. GRONOVITS, Zoophyladuin gronovianam, 17M, \>. 357. 

 tiiiiini'ixfii, ELLIS and SOLANDER, Nat. Hist. Zooph., 1786, p. 36. 

 Sertutaria tamarisca WILKINS and HERBST, Charakteristik der Thierpflanzen, 1787, p. 167. 

 Si-Hnliii-iii liiiiinrlxca GMELIN, Systema Natune, Liniueus, I, 1788-1793, p. 3845. 

 tii'rtuliii-ia liniiiirisfii. BERKEXHOI'T, Synops. Nat. Hist. Great Britain, I, 1789, p. 216. 

 Ki'1'lii/ni-iti tiniiiirixi-ii OLIVI, Zoologia Adriatica, 1792, p. 288. 

 Sertiilariit. linimrixcn. LAMARCK, Systeme des anim. sans Vert., 1801, p. 382. 

 i-iii liiiiinrixi'ii ISnsc, Hist. nat. des Vers, III, 1802, p. 92. 

 i-lii, lamarisca TURTON, British Fauna, 1807, p. 212. 



/iuiiirixcn LAMOUROUX, Bullet, Philonmtique, 1812, p. 184. 

 \'i<iflliixirinii (Sertutaria) tamariscaOKEV, Lehrbuch der Naturgeschichte, 1815. p. 93. 

 X rliiltn-in titi/Hii-ixi-ii IvAMoi-Koi-x, Hist. nat. des Polypiers, 1816, p. 188. 



'See explanation of this appearance on pp. 30-32. 



