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Gonosome. Goiiangicr |):i'i-ct'i)rnunl('. gliitte, mt'd en 

 kort rorfonuig Aabnin"-. 



Af dunne Art, som ikke tidligere er beskrevet, fandtes 

 under Nordh.-Exp. noglo Kolonier paa en enkelt Station. 



Kolonierne har en Hoide af 8 — 10 cm. og; er temme- 

 lig tæt besatte med Grene, der i Koloniens proximale Del 

 udgaar nogenlunde regelnuessig alternerende, og i et Plan. 

 I den distiile Del deriniod udgaar Grene i alle Retninger, 

 og de er atter selv forgrenede i Planer, der ligger lodret 

 paa Koloniens oprindelige Plan, og denne faar saaledes et 

 eiendommeligt buskformigt Udseende. Hovedstammen er 

 enkel, og utydelig leddelt og bærer, ligesom alle Grene, 

 Hydrotlieker. Grenene har tydelige Led, der er stillet 

 lodret paa deres Lrengdeaxe, og hvert Internodium barrer 

 et Par eller, mod Grenenes Spids, kun en Hydrothek. 



Grenenes to Hydrothekrækker ligger ikke i samme 

 Plan, men deres Planer danner en Vinkel paa ca. 90" med 

 hinanden, saa at naar man ser en Gren fra Siden, har 

 man alle Hydrothekei- udmundende ])aa samme Side af 

 denne. Grenene faar saaledes en Forside (med Hydro- 

 thekmundinger) og en Bagside. De horizontalt udbredte 

 Grene i Koloniens distale Del har alle sin Forside vendt 

 opad, mod Koloniens Spids. I Vinkelen ved Basis af 

 Grenene sees altid en Hydrotiiek. 



De to Hydrotheker. som staar paa samme Interno- 

 dium og danner et Par. staar ikke i samme Hoide, idet 

 som Regel den, der befinder sig paa Internodiets venstre 

 Side (seet langs Grenenes Forside fra dens proximale mod 

 den distale Ende), er mere distalt beliggende end den anden. 



Hydrothekerno er n;ermest tlaskeformige, idet deres 

 nederste Del er opsvulmet; deres cirkelrunde Aabning staar 

 lodret paa Grenenes, — og saaledes ikke paa deres egen 

 — Længdeaxe. 



Gonangier findes i tætte Rækker jjaa Forsiden af 

 Grenene, mest i Koloniens distale Del. De er pære for- 

 mede, næsten ret afskaarne i den distale Ende og med en 

 meget kort rorformig Aabning. 



Findested. St. 322. 



Dynamena tamarisca. Lin. " 



Trophosome. Hydrocaulus enkel, Grene alternerende. 

 Hydrotheker rørformige, modsat stillede, med tre ligestore, 

 stumpe Tænder om Randen. 



Gonosome. Hau : Sammentrykt fra Siderne, med 

 en rorformig Aabning og en liden Spids paa hver Side af 

 denne. Hnii: Pæreformet med tre Ribber udvendig. der 

 i den distale Del danner Basis for endel spidse Tænder, 

 der rager frem over JMundingen. 



Gonosome. Gonangia pear-shaped, sniooth, with a 

 sliort tubular opening. 



During the N. Atlan. Exp. a few colonies of this 

 species, which has not been previonsly describetl, were 

 found at one staticm. , 



The colonies are from 8 to 10 cm. higli, and are 

 rather tliickly beset with branches, which. in the proximal 

 part of tile colony, alternate with a ccrtain regularity, and 

 in one plane. In the distal portion, on the otlier hand, 

 tlie bi'anches stretch in all directions, and branch in their 

 turn in planes which are at right angles to the original 

 plane of the colony, thus imparting a peculiarly bushy 

 appearance to the colony. The chief stem is single and 

 indistinctly articulated. and, like all the branches, bears hy- 

 drothecæ. The branciies are distinctly joint ed, the joints 

 being placed at right angles to their long axis, and each 

 internode bears of pair af hydrothecæ, or towards the end 

 of the branch, one. 



The In-anches' two rows of hydrothecæ do not lie in 

 the same plane, but their planes form an angle of about 

 60" with one another, so that in a side view of a branch, 

 all the liydrothecæ open upon one side. Tiie branches 

 tlius have an anterior and a posterior side. the anterior 

 having the openings of the hydrothecæ. The horizontal 

 branches in the distal portion of the colony have their 

 anterior side turne 1 npwards, towards the apex of the co- 

 lony. There is always a hydrotheca in the angle at the 

 base of the branches. 



Tiie two hydrothecæ that stand on the same inter- 

 nijde, and form a pair. are not exactly opposite one an- 

 other; for, as a rule, the one on the left side of the inter- 

 node (looking along the anterior side of the branch, from 

 its proximal towards its distal end), is more distally situated 

 than tiie other. 



The hydrothecæ are almost bottle-shaped, their lower 

 portion being swollen; and tlieir circular opening is per- 

 pendicular to tiie branclvs. and therefore not to tlieir 

 own, axis. 



Gonangia are found in close rows upon the anterior 

 side of the branch, chiefly in the distal part of the colony. 

 They are pear-shaped, almost abruptly truncated at their 

 distal end, and with a very sboi-t tubular opening. 



Iiocality. Station 322. 



Dynamena tamarisca. Lin. 



Trophosome. Hydrocaulus simple, branches alterna- 

 ting. Hydrothecæ tubular, placed opposite one another, 

 with three equal, lilunt teeth on the margin. 



Gonosome. Male: compressed laterally, with a tubular 

 opening, and a little spike on each side of it; female: pear- 

 shaped, with three external ribs, which form, in their 

 distal portion, the foundation for some pointed teeth, wiiich 

 project over the oiieiiing. 



Den norske Noi-dlLivsexpeditiou. Kristine Bonnevie: Hydroida. 



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