08 



smukt rosenrøde, paa den adorale Flade lysebrune. Mund 

 tentaklerne ere smukt kastaniebrune, ligesaa Mundskiven 

 med lysere Straaler, Tab. V, Fig. 8, 9. 



Roret, hvori Cerianthus Vogti bor. er ikke synderligt 

 længere end Kroppen. Det er ganske lukket forneden, 

 og foroven er der en Aabning, stor nok til at Dyret kan 

 strække sig ud og fcrække sig ind, naar det vil skjule sig. 

 Da Koret er saa kurt. at Dyret med dets Tentakler ikke 

 uden at trække sig betydelig sammen kan skjule sig deri. 

 sker denne Sammentrækning spiralformigt . saa at Dyret 

 ligger i en Spiral inde i Roret. Dette er udvendigt ujevnt 

 og sammensat af brunagtigt Ler med iblandet Sand ; men 

 paa dets indvendige Flade er det beklædt med en glat, 

 glinsende Slimmembran, der er temmelig stærk. 



Ved Tversnit at Kropshuden sees. at denne er dan- 

 net af et Ectoderm, som bestaar al lange, smale Cylinder- 

 celler med deres Kjerne og Kjernelegeme, Tab. XXV. 

 Fig. 7 b. imellem hvilke er en stor Mængde kolbeformede, 

 encellede Slimkjertler, Tab. XXV. Fig. 7 r. samt Nema- 

 tocyster. Ectodermets ydre Flade er dækket af en struk- 

 turløs Cuticulå, Tab. XXV, Fig. 7 a. Indenfor Ectodermet 

 er et bredt Lag af Længdemuskler, der danne Bundter, 

 Tal». XXV. Fig. 7 d, som ligge dels ganske tæt til 

 hverandre, dels saavidt spredte, at Cylindercellerne med 

 deres smale, indre Ender kunne træde imellem, Tab. 

 XXV. Fig. 7 e. Dette Muskellag stoder umiddelbart til 

 Bindevævet, hvortil det er fæstet, og som er hyalint. tem- 

 melig smalt og kun ringe forsynet med Bindevævslegemer 

 og Ernæringskanaler, Tab. XXA . Fig. 7 f. Paa dette 

 Bindevævs (Mesoderms) indre Flade ligge Tvermusklerne, 

 der beståa af enkelte Fibre, som danne en tynd Lamel, 

 Tab. XXV. Fig. 7 <i. og ere kun lidet udviklede, imedens 

 Længdemusklerne ere særdeles stærke; Tvermuskellaget er 

 beklædt af Endothelet. 



Svælgrøret er eylindrisk, omtrent 20*"" langt. Paa 

 dets indre Væg iagttages 2 Svælggruber, der af Heider 

 benævnes den store og lille Mundviukelgrube, og som alle- 

 rede af Haine er iagttaget. Den store Svælggrube er paa 

 Grund af sin Form og Størrelse strax ioinefaldende, naar 

 Svælgrøret aabnes efter Længden. Den følger BugHaden, 

 har en dyb Rende i Midten, og til begge Sider af denne 

 er en bred, glat Vold, der strækker sig omtrent 1""" til 

 Siden, hvor Svælgrøret er stærkt foldet efter Længden. 

 Tab. XXV, Fig. 8 a. Ligeoverfor den store Svælggrube 

 er den lille, som svarer til Rygsiden og derfor kan kaldes 

 den dorsale Svælggrube. Denne er kun lidet dyb og tem- 

 melig trang, men giver sig dog tilkjende ved sit glatte 

 Udseende, Tab. XXV, Fig. 8 b, i Modsætning til Side- 

 partierne, der ere stærkt foldede. Tab. XXV, Fig. 8 c. 



their aboral surface, a beautiful rose-red ; on the adoral 



surfaee light brown. The oral tentacles as well as the 



oval disc are beautiful chestnut brown, the latter having 

 lighter-coloured radii (Pl. V, figs. 8, 9). 



The tube, in whic.h Cerianthus Vogti dwells, is not 

 much longer than the body; it is quite closed at the foot. 

 hut at the top there is an opening sufficiently large to 

 admit of the animal extendiug itself out and retracting 

 itself inside again, when it desires to conceal itself. As 

 the tube is so short that the animal, with its tentacles. 

 cannot, without contracting itself greatly together. conceal 

 itself in the tube. the contraction proceeds spirally, and 

 the animal lies coiled like a spiral in the tube. The 

 tube is rough externallv. and is composed of brownish 

 clay with sand mixed in it; on its interior surface, however, 

 the tube is coated with a smooth shining mucous-membrane. 

 which is pretty strong. 



Opon transversal section of the integument of the 

 body it is seen. that the integument consists of an ecto- 

 derm consisting of long narrow cylinder-cells with their 

 nuclei and uucleus-corpuscles (Pl. XXV. fig. 7 6), between 

 which there are a great multitude of claviform, unicellular 

 mucous glands i Pl. XXV. fig. 7 c), and also nematocysts. 

 The nuter surface of the ectoderm is covered by a struc- 

 tureless cuticulum (Pl. XXV, fig. 7 a). On the inside of 

 the ectoderm there is a broad laver of longitudinal inuscles 

 that form fasciculi (Pl. XXV, fig. 7 d), which he. partly 

 quite close to eacb other, but partly so widely distributed 

 that the cylinder-cells with their narrow, inner extremities 

 appear visible between (Pl. XXV, fig. 7 e). This mus- 

 cular layer unites immediately to the connective-tissue, 

 to which it becomes attached, and which is hyaline. rather 

 narrow, and only poorly furnished with connective-tissue 

 corpuscles and nutritory ducts i Pl. XXV. fig. 7/). Upon 

 the inner surface of this connective-tissue (mesoderm) the 

 transversal muscles are placed ; they consist of single fibres 

 that form a thin lamella (Pl. XXV. fig. 7 r/i. and are only 

 little developed, while the longitudinal muscles are par- 

 ticularly strong. The laver of transversal muscles is clothed 

 with the endothelium. 



The icsophagus is cvlindrical, and measures about 

 20'"'" in length. Upon its inner wall 2 gullot-grooves are 

 observed; these have been termed by Heider, the great 

 and the little oral-angle-cavities, and they have already been 

 noticed by Heine. The great gullet-groove is, owing to its 

 form and size. immediately prominent to the eye when the 

 æsophagus is dissected longitudinally. It follows the ventral 

 surface. has a deep channel in the middle, and on both 

 sides of this channel there is a broad, smooth rampart 

 that, for about 1""". extends itself to the side. where the 

 gullet-tube is strongly folded longitudinally (Pl. XXV. 

 fig. 8 a). Just opposite the great gullet-groove is the 

 small one, which corresponds to the dorsal side and may, 

 therefore, be termed the dorsal gullet-groove. This is of 

 only little depth and pretty narrow. but vet it makes itself 

 apparent by its smooth appearance (Pl. XXV. rig. 8 li) 



