fi32 Mil. J. niTciiii: (IN iiVDROiDS [M:iy21, 



TiiiiAUiA TUUULiFOKMis Muiktaniier. 



181)0. Dipiamenaiuhidiformis Maiktanner-Tunieretscher, Ann. 



k.k. Hofmus. Wfen, vol. v. p, 238, pi. iv. fig. 10. 

 Only a few colonies of this species, the largest 15 mm. high, 

 were found. The structures are typical, and agree more closely 

 with Mark tanner's and with Nutting's* figures than with those 

 of Natal speciuions by Wan-en t, in which the hydrothecre are 

 shown tabe less crowcled, and are more seldom arranged in groups 

 of several pairs. Our specimens show all the peculiarities of 

 arrangement of hydrothecfe on the stem internodes which IVIark- 

 tanner cites. Most commonly, as in Nutting's specimens, each 

 istem-internode bears " a branch and two hydrothec?e on one .side 

 and a single hydrotheca on the other," but occasionally, as Clarke + 

 also has found, a hydi-otheca-pair is adtled to this ty})ical inter- 

 node, and occasioniilly a hydrotheca-pair is sulrf.mcted and 

 isolated on .a separate internode, leaving one hydrotheca with 

 its iissociated branch -process alone on an internode. 

 Dimensions : — 



Length of colony up to 15 mm. 



T3'pical stem internode, length 1 1)6 mm. 



Stem internode, diameter O'lS-O'.'H mm. 



Branch, length about 5 mm. 



Hydrotheca, length of adnate portion 0'42 mm. 



„ ,, free „ 0-11 -O'lo mm. 



„ diameter 0'14 mm. 



Loculitif. Reef, Flying-Fish Cove, 



This species has now l)een found in the Eastein Pacific Ocean 

 (Perico Island, Gulf of Panama — Clarke, 1907); in the Western 

 Atlantic Ocean (Bahia; Florida; Bahama Banks— Nutting, 1904) ; 

 in the Eastern Atlantic Ocean (St. Tliomas Island — Billaid. 1907) ; 

 in the Red Sea (Jidda — Marktanner, 1890; Suez; Bay — Thornely, 

 1908); from the West Indian Ocean (Natal — Warren, 1908); and 

 now from the East Indian Ocean. Pictet has recorded from 

 Amboyna, in the East Indies, specimens which he ha.s named 

 Sertularia ve<ja' (Thompson), as a synonym of which he i-anks 

 Dipiamena ixbHliforinis Marktanner §. With Jiiderholm 'i, I am 

 of opinion that these specimens are not to be identilied with 

 T. veyce. They clearly belong to 7'. tuhulifonnis. 



Family P i, r m r i, a u i n .«. 



PlUMULAUIA UbSKII Bale. 



1884. Plmtndaria bnskii Bale, Cat. Australian Tlydroid Zooplu, 



Sy<lney, p. 124, pi. x. fig. '.i, pi. xix. iigs. 'M, 3;"). 

 Several colonies occurred growing on a sjiouge. They aic much 



• Nutting, " Anicricin Hydroirls," Spec. Ihill. Smitlis. Inst., Part 2, 1901-, pi. xi. 

 fiRs. 1. 2, ;?. 



t Wiivrcn, op. cit. p. 31.i, toxt-tijr. 12. 



J ("Imku, Mem. Mu«. Cnnip. Zool. Hiivvunl, vol. xxxv. 15)07, p. H. 



:;• I'ii'tf't, U<v. Suisse rip Zoot. vol. i. IMSW. p. \L 



li .Iddcvliohn, Kiuifrl- «veii>ka Vtt.-Ak. Manill. vol. xlv. lOOO, p. 91. 



