126 



kornet Masse, uden at nogen Kjerne kan iagttages i dem og 

 ligne meget de hvide Blodlegemer hos de høiere Dyrklasser. 



Polypkroppen er udvendigt beklædt med et Ectoderm, 

 meget ligt elet. som tindes paa Stammen og Grenene. 

 Fig. 4. a. og hvori encellede Slimkjertler og Spikler ere 

 leirede. Indenfor Ectodermet er et Bindevævslag, Fig. 4. e, 

 der svarer fuldkomment til det. som er beskrevet ved 

 Stammen. Det samme Maskenæt findes her; Maskernes 

 Vægge ere overtrukne med Ectodermceller, Fig. 4. c. og 

 Hulhederne fyldte med Spikler. Fra Bindevævets ind- 

 vendige Flade udgaa 8 Septa. der fæste sig paa Svælget 

 og danne Kamrene. Muskelanordningen paa Septa er sum 

 sædvanlig; ligeledes ere Kamrene overalt forsynede medet 

 Lag runde Celler med Kjone og Kjernelegerae. Fjg. 4. /. 



Svælget er langt, cylindrisk, uden Spikler, Fig. 5, a : 

 paa dets indre Flade er langs Bugsiden en temmelig vid, 

 halvrund Svælgrende, forsynet med lange Pidskeceller, Fig. 

 4. //; den øvrige Del af Svælget er beklædt med eilierende 

 Celler, hvoraf de i den øverste Del nærme sig meget Ecto- 

 dermcellerne uden at være saa kantede, imedens de i den 

 nedre Del maa betragtes som Cylinderceller. Overalt i 

 Svælgepithelet, naar undtages Svælgrenden, er indplantet 

 dels pæreformige, dels ægformige, encellede Slimkjertler i 

 temmelig stor Mængde; Fig. 4. h. Disse Slimkjertler have 

 en smal Udførselsgang, der munder ml i Svælghulheden. 



Kjønsorganerne sidde langt nede i Mavehulheden og, 

 som tidligere nævnt, træffes de ogsaa i Kanalerne saavel 

 i Stammen som i Grenene og have den samme Bygning, 

 som oftere er omtalt. Kjønnet er adskilt. Hos tirre 

 Polyper vare Embryonerne endnu indesluttede i Ægget, 

 hvor de laa stærkt bøiede, Fig. 6; hos andre havde de 

 forladt Ægget. laa frit i Mavehulheden, vare temmelig 

 lange, ormformige, overalt beklædte med Cilier og forsynede 

 med Gastrulamave og Mund. Hos disse frigjorte Embryoner 

 iagttoges endnu ikke nogen Spikeldan neise, saaledes som 

 Tilfældet var hos Embryonerne af Slægten Nephthya, og 

 der er Grund til at antage, at Spiklerne forst optræde, 

 efter at Ungen har forladt Moderen for at fore et selv- 

 stændigt Liv; thi hos en Polyp var netop en saadan 

 spikelløs Unge ifærd meil at passere igjennem det trange 

 Svælg for at paabegynde sit individuelle Liv. Fig. ."). 1. 



Paa Basaldelen ligge Spiklerne pakkede paa hver- 

 andre, og de hyppigste Former, hvorunder de her optræde, 

 ere Firlinger, Dobbeltstjerner og Spindler. Firlingerne 

 ere meget forskjellige, kors-, timeglas- eller rosetformede ; 

 de ere dels glatte, dels -,vaut besatte med Papiller, dels rigt 



the duets have, partly, the same form. size. and substance 

 as the endothelial cells or. partly. they are a little 

 different from them. owing to their being filled up witli a 

 granular mass in whieh no nuclei can be detected, and 

 much resembling the white blood-corpuscles found in the 

 higher classes of animals. 



The polyp-body is. externally, clad with an ectoderm 

 much resembling that found on the stem and the branches, 

 (fig. 4. a), and in whieh unicellular mucous glands and 

 spicules are embedded. Inside of the ectoderm. there is 

 a connective-tissue layer (fig. 4. é) whieh exactly corre- 

 sponds with that described in connection with the stem. 

 The same reticulation of meshes is found here; the walls 

 of the meshes are coated with ectodermic coils (tig. 4. r). 

 and the cavities are filled with spicules. From the interior 

 surfaces of the connective-tissue, 8 septa issue and attach 

 themselves to the gullet, and form the ducts. The museu- 

 Ur ai*rangement on the septa is the usual one, and the 

 chambers are. also, everywhere supplied with a layer of 

 globular cells containing nucleus and nucleoli (fig. 4. /). 



The gullet is long. cylindrical, and devoid of spicules 

 (fig. 5, a). On its inner surface, along the ventral side. 

 there is a pretty wide, semi-circular, gullet-passage furnished 

 with long flagelliform cells (fig. 4. >/). The remaining part 

 of tlie gullet is clad with eiliated cells, of whieh. those in 

 the uppermost part approach much. in form. to the ecto- 

 dermic cells. without. hovvever, being so angular. whilst 

 those in the lower part must he considered to be cylinder- 

 cells. Everywhere. in the epithelium of the gullet, with 

 exception of the gullet-passage. there are planted, partly 

 piriform, partly oviform, unicellular mucous glands in 

 pretty great abundance (tig. 4. //). These mucous glands 

 have a narrow excretory duct whieh opens into the gullet- 

 c.avity. 



The generative organs are placed far down in the 

 gastral cavity. and. as previously stated, they are also met 

 witli in the ducts of. both, the stem and the branches. and 

 have the same structure as that alreådy frequently spoken 

 of. The sexes aiv separated. In ma ny polyps. the em- 

 hryons were still ehclosed in the oyum, where they lay 

 st rongl v curved (tig, 6). In others. they had emerged from 

 the oviini and lay loose in the gastral cavity. appearing 

 pretty long. flat and verniiform. and clad all over with eiliæ ; 

 and also furnished with a true gastrula sto mach and mouth. 

 In these independent embryons, no spicular formation was 

 vet visible, like the case of the emhryons of the genus 

 Nephthya, and there is reason to suppose that the spicules 

 first appear after the young one has abandoned the mother 

 in order to lead its independent life. because, in one polyp, 

 one of these spieule-free young ones was just engaged in 

 passing through the narrow gullet in order to start upon its 

 individual existence (tig. ,">. h). 



In the basal part. the spicules are placed packed 

 upon each other, and the most frequent forms in whieh 

 thej appear. here. are quadruplets, bistellates and fusees. 

 The quadruplets are very various in form. as they are met 

 with in cruciform, sand-glass form. or rosetiform ; thev 



