61 



Væringia og Duva, og paa drivs V, egge iagttages store, 

 ovale Aabninger for hver tilstødende Gren, hvorved dennes 

 Kanaler kommunicere med Stammens. Længdekanalernes 

 Vægge, eller den indre Bindevævsflade, er beklædt som 

 sædvanlig! med Længde- og Tvermuskler, der have et 

 Epithelovertræk, bestaaende at' rumle Celler. 0.010°"° store, 

 med en rund Kjerne, omgiven af Protoplasma. Paa 

 Bindevævets ydre Flade, imellem denne og Ectodermet, er 

 overalt indleiret Kalkspikler. der ere forskjellige i Form 

 og Størrelse paa de forskjellige Steder af Stammen og 

 Grenene, og som senere skulle beskrives. 



Polyperne ere paa deres ydre Flade beklædte med et 

 Ectoderm, ligt det. sum tindes paa Stammen og Grenene, 

 — kun ere Cellelagene ikke saa mange, ligesom Gellerne 

 i det indre Lag ere rundere og rigere paa Protoplasma- 

 indhold end i de ydre Lag, Fig. 6, a. Ogsaa her tindes 

 lignende Slimkjertler som paa Stammen, Fig. 6, b. Indenfor 

 Ectodermet er et bredt, hyalint Bindevævslag. rigt paa 

 Ernæringskanaler med deres Endothel, og paa dette Binde- 

 vævs ydre Flade, dækket at' Ectodermet. er den store Mængde 

 af Spikler indleiret, der omgiver hele Polypkroppen, 

 Fig. 6, c. Fra Bindevævets indre Flade udgaa de 8 

 Septa. der heste sig paa Svælget, Fig. 7, a. og derfra 

 forhenge sig langs hele Mavehulheden under Navn af 

 Septula, De beståa af en Bindevævslamel, paa hvis ene 

 Side er fæstet longitudinelle og paa den anden Side trans- 

 verselle Muskelfibre, Fig. 7. h, c. Disse Muskelfibre ere 

 Fortsættelser af Muskellaget paa Bindevævets indre Flade, 

 ligesom de gaa over paa Svælgets ydre Flade og udbrede 

 sig deri, Fig. 7. Hele Mavehulheden med Septa og Sep- 

 tula er beklædt med et Epithel, der dannes af to Lag 



runde Celler. 0.009 store, som have en tynd Membran, 



en rund Kjerne. 0.004""" stor, omgiven af kornet Proto- 

 plasma. Fig. 7. <1. 



Svælget er cylindrisk. foldet, temmelig langt og 

 paa sin ydre Flade beklædt med Epithel af samme Be- 

 skaffenhed som det. der tapetserer hele Mavehulheden. 

 Om det danner flere Lag af Celler kan ikke afgjøres med 

 Sikkerhed; men paa enkelte Steder havde det Udseende af 

 to Lag, paa andre af et. Dækket af dette Endothel ud- 

 brede de tidligere omtalte Retraktores og Protraktores sig 

 paa et hyalint Bindevævslag. der som sædvanligt er for- 

 synet med Ernæringskanaler og Bindevævslegemer med 

 Udløbere. Paa dette Bindevævs indre Flade er Svælgets 

 egentlige Muskellag. der dannes af longitudinelle men 

 væsentligst af paaskraas gaaende, cirkulære Fibre, og er 

 beklædt med Epithel. som umiddelbart støder til Svælg- 

 hulheden. Dette Epithel er paa den øverste Trediedel og 

 forøvrigt til Siderne en Fortsættelse af Kroppens Ecto- 

 derm, men er dog noget modificeret, idet Cellerne ere 

 mere langstrakte, ikke saa kantede, og imellem disse sees 



the genera Væringia and Duva. On their walls, large oval 

 apertures for each adjacent brancb are observed. by which 

 its ducts communicate with those of the stem. The walls 

 of the longitudinal ducts, or the inner connective-tissue 

 surfaces, are clad. as usual, with longitudinal aud trans- 

 versal muscles which have an epithelial eovering. eonsist- 

 ing of cylinder cells measuring 0.010""" in diameter and 

 containing a round nucleus enclosed by protoplasm. On the 

 outer surface of the connective tissue. between it and the 

 ectoderm. calcareous spicules are, everywhere, entrenched; 

 these varv in form. and size in the different parts of the 

 stem and the brancb.es, and will be, subsequently, described. 



On their exterior surface, the polyps are clad with 

 an ectoderm like that which is found upon the stem 

 and the branches, only, the cellular layers are not so 

 numerous, whilst, also, the cells in the inner laver are 

 more cylindrical and richer in protoplasmic contents 

 than those in the outer laver (fig. li. <i). Also, in 

 this situation. mucous glands like those of the stem 

 are found (fig. 6, b). Inside of the ectoderm. there 

 is a broad laver of hyaline connective tissue, rich in nutri- 

 tory ducts with their endothelium. and on the exterior 

 surface of that connective tissue. covered by the ectoderm. 

 the large mass of spicules which surround the entire body 

 of the polyp are entrenched (fig. 6, c). From the inner 

 surface of the connective-tissue proceed, the 8 septa, 

 which are adherent to the gullet (fig. 7, a) and prolong 

 themselves, thence, along the entire ventral cavity, under 

 the form of septula. They consist of a connective-tissue 

 lamella on whose one side, longitudinal, and on the 

 other side transversal, muscular fibres are secured (fig. 7, 

 b, c). These muscular fibres are continuations of the 

 muscular layer of the inner surface of the connective- 

 tissue. whilst. also. they are produced, over, into the 

 exterior surface of the gullet and spread themselves there 

 (fig. 7). The entire ventral cavity. with septa and septula, 

 is clad with an epithelium, formed of two layers of cylin- 

 der cells measuring 0.009 in diameter, having a thin 



membrane, and containing a round nucleus measuring 

 0.004 enclosed by granular protoplasm (fig. 7. d). 



The gullet is cylindrical, folded, rather long. and. 

 upon its exterior surface, it is clad with epithelium of the 

 same character as that which lines the entire rentral 

 cavity. Whether it forms several layers of cells cannot, 

 with certainty, he decided; in a few places there was 

 the appearance of two lavers, but in others, again. only of 

 one. Covered by this endothelium, the previously men- 

 tioned retractors and protractors spread themselves upon 

 a hyaline connective-tissue-layer which. as usual, is furnished 

 with nutritorv ducts and connective-tissue corpuscles with 

 prolongations. On the inner surface of this connective- 

 tissue, the real muscular laver of the gullet appears; it is 

 formed of longitudinal, but chiefly of diagonally running, 

 circular fibres, and is clad with epithelium which connects 

 immediatelv to the gullet cavity. This epithelium is. 

 on its uppermost third part. and otherwise, also. on its 

 sides, a coiitiimation of the ectoderm of the body, but is. 



