38 



lignende Function af Be skj ærmeise for de øvrige Vedhæng, 

 som Dækbladene, hvilke her fattes. Den omhandlede Fø- 

 letraad er i contraheret Tilstand fra halvt indtil ligesaa 

 lang som Føleren, simpelt cylindrisk med smalere tilrundet 

 Ende, og viser et Antal ringförmige Indsnøringer, der, som 

 Claus udtrykker sig, se ud „som Leddene af en Bæn- 

 delorm." 



Paa den ydre Ende af Følerne bemærkes under Mi- 

 kroskopet en Hob af omtrent 20 langstrakt-ellip tiske Nes- 

 selceller (Fig. 21), der indslutte en Nesseltraad af ualmin- 

 delig Størrelse. Denne Traad er nemlig, naar den er 

 traadt ud af Cellen og strakt, mere end 1 Mm. lang eller 

 omtrent V 4 af Følerens Længde; den er bøielig, besat med 

 overmaade smaa runde Knuder, og sidder paa Enden af 

 et næsten dobbelt saa tykt, cylindriskt, stivt Skaft, som 

 rager frem udenfor Enden af den tomme Celle, og omtrent 

 er saa langt som denne. Dette Skaft (Fig. 22) er i dets 

 nederste Halvdel tæt omgivet af en tynd Hud, som i den 

 øverste Del staar langt ud fra Skaftet og antager en ten- 

 dannet Form af dobbelt saa stor Brede som dette; Over- 

 fladen af denne Hud viser talrige, overmaade fine tætte 

 krumme (med Concaviteten nedad vendte) Tværstriber. 

 Yderst ender Skaftet i 2 Spidser eller Smaapigge, hvilke 

 omfatte Basis af den fra dets Top og som en umiddelbar 

 Fortsættelse af denne udgaaende bløde Nesseltraad, og er 

 omtrent ved Midten af dets Længde besat rundtom med 

 et større eller mindre Antal af tilspidsede Børster eller 

 Pigge, der ere 7 4 — x / 3 af Skaftets Længde og rettede 

 skraat opad og udad. 



SUGERØRENE. 



Sugerørene eller de polypagtige Maver (polypites, Hux- 

 ley) sidde nederst paa den ydre Bue af Skivens Spiral et 

 lidet Stykke ind paa Underfladen. De vare, som allerede 

 ovenfor anført, hos mit største Exemplar alle affaldne med 

 Undtagelse af et større (Fig. 1—4, a), som udstrakt var 

 15 Mm. langt og i contraheret Tilstand 9 Mm. laugt og 2 

 Mm. tykt, og et andet flere Gange mindre i Nærheden af 

 Vegetationspunktet. Begge havde den sædvanlige lang- 

 strakte eller næsten cylindriske, i et inderste (Basaldelen), 

 et mellemste (Maven) og et yderste Afsnit (Snabelen) af- 

 delte Sækform. Mærkerne af de affaldne Sugerør vare 

 imidlertid synlige som en Rad af 16 — 18 lave (de største 

 % Mm. lange) coniske Knuder (Fig. 3, b b, Fig. 7) paa 

 Skivens Underside nær ved den ydre Rand eller i nogen 

 Afstand fra Kjønsknopperne; de aftage i Størrelse heni- 

 mod den smalere Ende af Skiven, hvor de synes at fattes 

 under de nærmest ved Vegetationspunktet fremspirende 

 Kjønsvedhæng. Disse Knuder ere knopformige Fremrag- 

 ninger af Skiven, paa hvilke Sugerørene ere fæstede og 

 maa ikke forvexles med disses hyppig rundagtige Basaldel. 

 Forresten syntes Sugerørene ikke at staa i lige Linie med 

 Kjønsvedhængene, men heller med disses Mellemrum. Hos 

 mit mindste Exemplar, som neppe var halvt saa stort som 

 hint, vare Sugerørene (Fig. 23, a a, Fig. 24, vel bevarede 

 og af rødlig Farve; de største vare i udstrakt Tilstand 10 



reason be said physiologically to perform the same func- 

 tion in protecting the other appendages as the scales 

 which are here wanting. The filament mentioned is in 

 its contracted state' from half to quite as long as the 

 feeler, simply cylindrical with a taper rounded extremity 

 and shews a number of annular instrictions , which, as 

 Claus expresses himself, "look like the joints of a tape 

 worm." On the outer extremity of the feelers, there 

 appears under the microscope a cluster of about 20 

 elongated elliptical thread-cells (fig. 21) which inclose 

 an urticary filament of unusual size. This filament is, when 

 protruded from the cell and extended, more than 1 Mm. 

 long, or about 7 4 of the length of the feeler; it is flexible, 

 covered with extremely small round tubercles and situated 

 at the extremity of a cylindrical stiff shaft, nearly twice as 

 thick, projecting beyond the empty cell and about as long 

 as the latter, The lower half of this shaft (fig. 22) is close- 

 ly surrounded by a thin membrane, which in the lowest 

 part stands far out from the shaft and assumes a fusiform 

 shape of twice the width of the shaft. The surface of this 

 skin shews numerous extremely fine close transverse stripes 

 curved with the concavity turned downward. At its out- 

 ward extremity, the shaft terminates in 2 points or small 

 spikes enclosing the base of the soft urticary filament that 

 issues from its top in immediate continuation; and about 

 in the middle of its length it is covered round about with 

 a greater or less number of pointed bristles or spikes 

 which are x / 4 — */ 3 of the length of the shaft, and directed 

 obliquely upwards and outwards. 



THE SUCTION-TUBES. 



The suction-tubes or the polyp-like stomachs (polypites 

 Huxley) are situated on the lowest part of the exterior 

 curve of the spiral of the disc, advancing a little on to the 

 under-surface. They had, as already previously mentioned, 

 all fallen off in my largest specimen with exception of a 

 larger one (fig. 1 — 4, a) which when extended was 15 Mm. 

 long, and when contracted 9 Mm. long and 2 Mm. thick, 

 and another many times smaller in the vicinity of the 

 vegetation-point. Both had the usual elongated or nearly 

 cylindrical sack-form divided into an inner section (the basal 

 part) a middle section (the stomach) and an exterior sec- 

 tion (the proboscis). The vestiges of the fallen suction- 

 tubes were however visible as a row of 16—18 low conical 

 tubercles (the largest % Mm. long) (fig. 3 bb, fig. 7) 

 on the underside of the disc, near to the exterior mar- 

 gin or at some distance from the sexual buds; they dimi- 

 nish in size towards the smaller end of the disc, where 

 they appear to be wanting under the nascent sexual ap- 

 pendages nearest to the vegetation-point. These tubercles 

 are knob-like prominences of the disc, on which the suc- 

 tion-tubes are fixed, and must not be confounded with the 

 often roundish basal part of the latter. Moreover the suc- 

 tion tubes did not appear to stand in a right line with the 

 sexual appendages, but rather in a line with their inter- 

 vals. In my smaller specimen, which was scarcely half as 



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