24 



men fra alle øvrige bekjendte Former, at den vistnok maa 

 danne ikke blot en egen Slægt, men en egen Familie 

 iblandt Hydroiderne. 



Dyrets Længde eller Høide er 1 — 1£", Bredden eller 

 Tykkelsen T \ — T y, altsaa colossale Dimensioner for en 

 Hydroide ; i contraheret Tilstand er det dog kun halvt 

 saa langt, men saameget tykkere. — Det forefindes altid 

 enkelt eller ene, aldrig, som saa almindeligt blandt Hy- 

 droiderne, flere Individer forenede sammen til en Coloni. 

 Dets Krop (Fig. 29, 30) er nøgen eller uden Polypstok, 

 kjødagtig, cylindrisk, oventil noget tykkere, altsaa ganske 

 lidt kølleformig, og paa denne tykkere ydre Ende (Fig. 

 29, d) forsynet med en liden cirkelrund Mundaabning, 

 som dog kan udvides betydeligt; den nederste Ende eller 

 Basis er smalere og udsender udadtil en Del frie stolon- 

 agtige Traade (Fig. 29, 30, a, b) af samme bløde Beskaf- 

 fenhed som Kroppen, hvilke med deres ydre Ende (b) 

 ere fastvoxne til et eller andet fremmed Legeme, hvortil 

 Dyret saaledes bestandig forbliver fæstet (se Fig. 30). 

 Den øverste Halvdel af Kroppen er overalt rundtom be- 

 sat med meget talrige (sikkert flere end 100), uden nogen 

 vis Orden adspredte Tentakler (Fig. 29, 30, c c, Fig. 31), 

 hvilke ere meget smaa og korte (i udstrakt Tilstand (Fig. 

 29) neppe saa lange som Halvdelen af Knoppens Tykkelse), 

 cylindriske og ende med en tykkere kugleformig Knop 

 (Fig. 31, c), som indeslutter talrige Nesselkapsler. Krop- 

 pens nederste Halvdel, som mangler Tentakler, er besat 

 med talrige Kjønskapsler, eller, rettere sagt, Kjønsdyr 

 (Fig. 29, g, g). Disse have (Fig. 32), ligesom hos Coryna 

 sqvamata og andre lignende, en kugledannet Form uden 

 Aabning, og indslutte en næsten halvt ind i deres indre 

 Hule fremragende cylindrisk eller noget kølleformig Axe 

 (b) (saakaldet Mave), som er en Fortsættelse af Kapse- 

 lens Stilk (s), hvilken igjen er en Fortsættelse af Moder- 

 dyrets eller Ammens Krop (Tarmrør, Loven). Mellem 

 denne Axe og Kapselens ydre temmelig tykke og gjen- 

 nemsigtige Hud (p), som viser en dobbelt Contour (se 

 Fig« 33, 34, p), er det at Kjønsstofferne udvikle sig. — 



Hydr. Zoophytes p. 76, og det vistnok med Kette, troet af de oven- 

 anførte Grunde ganske at burde forkaste Blainville's Slægtsbenæv- 

 nelser som grundende sig paa en ganske forkjert Opfatning af dette 

 Dyr, og heller foretrække det af min Fader givne Navn Myriothela, 

 under hvilket først dette Dyrs sande Natur og Affinitet er bleven 

 opklaret. Denne Forsker feiler imidlertid ganske sikkert ved at 

 identificere den af ham beskrevne Form, der er identisk med Gosse's 

 Spadix purpurea (Ann. Nat. Hist , Vol. 12, p. 125), med min Faders 

 Myriothela arctica. Disse 2 Former ere, som man vil finde ved en 

 Sammenligning af den her meddelte Beskrivelse og de tilhørende 

 Figurer med samme i Hinck's Værk, meget forskj ellige, ja saa for- 

 skj eilige, at det ikke er usandsynligt, at de endog kunde repræsentere 

 forskjellige Slægter, Navnlig er det Tilheftningsmaaden og Gem- 

 mestilkenes Form, som er vidt forskj eilig hos begge. - Jeg har 

 troet her at burde gjengive ganske ordlydende den af min Fader i 

 Forhandl, ved de Skand. Naturf. Møde i Christiania 1856 meddelte 

 meget udførlige Beskrivelse af dette Dyr, med de fornødne Henvis- 

 ninger til Figurerne, da der ikke forefindes nogen udførligere Be- 

 skrivelse i Manuskript, og jeg selv ikke har havt Anledning til at 

 iagttage dette Dyr. 



Udg. Anm. 



all other known forms, that it must certainly be regarded 

 as a new genus, and even as a new family among the 

 Hydroids. 



The length, or height of the animal is 1 — 1*"; the 

 breadth or thickness T V~iV'; colossal dimensions for a 

 Hydroid; in its contracted state, however, it is only half 

 as long, but so much the thicker. It occurs always soli- 

 tary or simply; never, as so usual among Hydroids, in 

 a colony composed of many individuals collected together. 

 Its body (fig. 29, 30) is naked or without polypary, fleshy, 

 cylindrical, somewhat thicker at the upper part, or very 

 slightly clavif orm; and on this thicker extremity (fig. 29, 

 d) is a small circular oral aperture, which yet may be 

 greatly widened; the inferior extremity or base is more 

 slender; and from it there issue outwards a number of 

 free stolon-like filaments (fig. 29, 30, a, b) of the same 

 soft nature as the body, the outer extermities (b) of which 

 filaments are attached by growth to some extraneous 

 body; so that the animal remains constantly fixed (see 

 fig. 30). The upper half of the body is everywhere sur- 

 rounded with numerous tentacles (certainly more than 

 100) (fig. 29, 30, c c fig. 31) distributed without any evi- 

 dent order, very small and short, (when extended (fig. 29), 

 scarcely equal in length to half the thickness of the 

 body) cylindrical and terminating in a thicker globular 

 knob (fig. 31, c), which contains numerous thread-cells. 

 The lower half of the body, destitute of tentacles, is co- 

 vered with numerous sexual capsules, or more properly 

 speaking sexual animals, (fig. 29, g g). These have (fig. 

 32) as in the Coryna squamata and the like, a globular 

 form without aperture, and contain a cylindrical or some- 

 what claviform axis (b) (the so-called stomach), projecting 

 nearly half-way into their interior cavity, and being the 

 continuation of the stem of the capsule (s), which is again 

 a continuation of the body of the parent animal (intesti- 

 nal tube Loven). Between this axis and the outer rather 

 thick and transparent skin of the capsule (p), which skin 

 exhibits a double contour (see fig. 33, 34, p), the sexual 



rent from the form described by Fabricius. On the other hand 

 Th. Hincks has lately in his History of the British Hydr. Zoophy- 

 tes, p. 76, and certainly with good cause, thought proper, for the 

 reasons above assigned, to reject Blainville's generic denomination 

 as founded on an entirely wrong conception of the animal, and to 

 prefer the name, given to it by my Father, Myriothela, under which 

 the true nature and affinity of this animal were first elucidated. 

 This naturalist however certainly errs in identifying the form de- 

 scribed by him, which is identical with Gosse's Spadix purpurea 

 (Ann. Nat. Hist., Vol. 12, p. 125) with my Father's Myriothela arc- 

 tica. These 2 forms are, as may be ascertained by comparing the 

 description here communicated, and the accompanying figures, with 

 those given in Hinck's work, which are so very different that they 

 might well represent different genera. It is specially in the mode 

 of attachment and the form of the germ-stems, that so wide a 

 difference between the two is exhibited. I have thought it right 

 to give word for word the very elaborate description of this 

 animal communicated by my Father in Forhandl, ved de skand. 

 Naturf. Mode in Christiania 1856, with the necessary references to 

 the figures; as there does not exist any more minute description 

 of it in manuscript; and I have not myself had occasion to exa- 

 mine this animal. Note of Editor. 



