124 



kunde trykkes over i den anden Polyps Gastrovascularhulhed. 

 hvorved Kroppen svulmede stærkt op. Men hvor flere 

 Polyper hænge sammen, der er dette Kanalsystem noget 

 mere indviklet, idet nemlig Coenenchymet, Tab. XXII, 

 Fig. 1 /, der binder Polyperne sammen , er mere eller 

 mindre optaget af Kanaler, som udgaa fra Polypernes 

 Bund, Tab. XXII, Fig. 1 a. Disse Kanaler ere tildels 

 temmelig brede, Tab. XXII, Fig. 1 b, c, løbe i forskjellige 

 Retninger og ere beklædte med et cilierende Epithel, Tab. 

 XXII, Fig. 1 e. ligt det, der tapetserer Polypens Gastro- 

 vascularhulhed. 



Pindested. 



Statiou 190. 10 Exemplarer. 



— 290. Xogle Exemplarer. 



323. En stor Mængde Exemplarer. 



— 3(33. 20—30 Exemplarer. 



Det vil af Figurerne paa Tavle XXI sees, at det 

 er hovedsagelig fra Polypens nederste (bagerste) Ende — 

 dens Basaldel — at der udskyder nye Polyper. I Begyn- 

 delsen danner der sig ved Granden en liden, næsten rund 

 Knop, Tab. XXI, Fig. 6, og undersøger man nu denne 

 vordende Polyp, saa viser det sig. at Moderpolypen fra 

 dens Bund sender nogle Kanaler gjennem et yderst smalt 

 Coenenchym til Knoppen, der er en Udbugtning af dette, 

 og hvori endnu ingen Septadannelse har fundet Sted. 

 Efterhaanden som Knoppen voxer frem, antager den Cylin- 

 derformen, og naar den har naaet en Længde af nogle 

 Millimeter, Tab. XXI, Fig. 5, 8, sees de fuldstændige 

 Septa som yderst smale Lister, der rage kun lidet frem i 

 Hulheden. Imellem Moderpolypen og Ungen er der en 

 tydelig Grændse, som endog udvendig giver sig tilkjende 

 ved en ringformig Fortykkelse. der danner Coenenchymet 

 imellem begge Polyper, Tab. XXI, Fig. 7. Naar nu den 

 unge Polyp er voxet end mere. gjennembrydes den fri 

 Ende, idet Mundskive, Mund og Tentakler ere dannede, 

 Tab. XXI. Fig. 1, 5, 8. De fuldstændige 'Septa, Macro- 

 septa, have dog vist sig i en hengere Tid. førend dette 

 Gjennemlirud tinder Sted; men det er at bemærke, livad 

 jeg forresten tidligere bar anført, at imedeus de fuldstæn- 

 dige Septa udgaa fra Polypens Bund. er dette ikke Til- 

 fældet med de ufuldstændige. 



Ofte bøier den unge Polyp sig under Yæxten, saa 

 at dens Basaldel sammen med Moderens danner en Bue, 

 Tab. XXI, Fig. 13. I Regelen er det kun en Knop, som 

 skyder ud fra Moderens Basaldel; men det hænder og, at 

 2 ja endog 3 udskyder derfra omtrent samtidigt, og da ind- 

 tager gjerne den ene en Sideplads, Tab. XXI, Fig. 1, ."). 7. 

 Iblandt den store Mængde Exemplarer, jeg har raadel 

 over, tindes mange, hvor kun to Polyper ere saninienfoiede, 

 og som muligens hele Livet igjennem forblive saaledes 

 parrede ; men endnu foregaar Kolonisationeii i ligere Maale- 

 stok, idet der fra de to Polyper udvoxer flere, Tab. XXI, 

 Fig. 3, 4, 9. Efterhaanden som de unge Polyper voxe, til- 



be easily forced into the gastro-vascular cavity of the other 

 polyp, causing the body to beeome considerably swollen. 

 But when several polyps are united this ductiferous system 

 is somewhat more developed, in so far, that the sarcosoma 

 (Pl. XXII, fig. 1 /) which unites the polyps together, is 

 more or less occupied by ducts that issue from the base 

 of the polyps (Pl. XXII, fig. 1 a). Tliese ducts are some- 

 times pretty wide (Pl. XXII, fig. 1 b, c), and run in var- 

 ious directions, and they are elad with a ciliating epi- 

 thelium (Pl. XXII, fig. 1 e) like that which coats the 

 gastro-vascular cavity of the polyps. 



Habitat. 



Station Xo. 190. Ten specimens. 



290. A fe\v specimens. 



323. A great lnany specimens. 



363. Twenty to thirty specimens. 



It will be observed from the illustrations on Plate 

 XXI. that it is principally from the lowest (posterior) ex- 

 tremity of the polyp that new polyps are produced. In 

 the commencement there is formed at the base, a small. 

 almost round bud (Pl. XXI. fig. ti), and if wc now examine 

 this prospective polyp, it is seen that the parent-polyp 

 sends out from its base a few ducts, through an extremely 

 narrow sarcosoma, to the offspring which is a protuberance 

 upon it. and in which no formation of septa has yet tåken 

 place. As the bud increases gradually in growth it 

 assumes the cylindrical form. and, when it lias attained a 

 length of a few raillimetres (Pl. XXI. fig. 5. 8), the perfed 

 septa beeome visible, like extremely narrow fillets that 

 only extend a little way into the cavity. Between the 

 parent-polyp aud the offspring there is a distinct demarca- 

 tion, which is even externally recognisable. by an annular 

 thickening that forms the sarcosoma between both polyps 

 (Pl. XXI. fig. 7). When, QOw,theyoung polyp has grown still 

 more, its free extremity becomes pierced, and the oral disc, 

 mouth and tentacles are formed (Pl. XXI. fig. 1. 5, 8). 

 The perfect septa (macrosepta) have. however, appeared for 

 some time previous to this perforation taking place; but 

 it is to be noted, what i also already have mentioned, 

 that while the perfect septa issne from the base of the 

 polyp. such is not the case with the imperfect ones. 



The young polyp often curves itself during its 

 growth, so that its basal part together with that of the 

 parent-polyp forms an are (Pl. XXI, fig. 13). Usually 

 there is only one bud that projects from the basal part 

 of the parent-polyp, but it happens, occasionally, that two, 

 indeed even 3, project from it at about the same time, 

 and then the one often occupies a lateral situation i Pl. 

 XXI, fig. 1, 5, 7). Among the very numerous specimens 

 I have had at my disposal, there are many in which only 

 two polyps are united, and which probably. throughout all 

 their existenee, remain thus paired; but yet the colonisa- 

 tion proceeds on an extended scale, inasmuch. that from the 



