86 



Embryonerne ere allerede tidligt meget rige paa 

 Spilder, og paa de fra Ægget frigjorte Unger, hvor Spikel- 

 dannelsen er meget stærk. saa at Spiklerne ligge paa 

 hverandre, iagttages mange og for skjelligtf ormede Firlinger, 

 Fig. 40. De fleste nærme sig Korsformen, ere fra 0.072 

 — 0.132""" lange, med en Tverstok fra 0.044—0.116'"'", 

 Fig. 41 — 51; kun enkelte nærme sig Timeglasformen og 

 ere 0.112""" lange, 0.052'""' brede mod Enderne og 0.020'"'" 

 brede paa Midten ; men hyppigere end Firlingerne ere 

 dog Spindlerne, som ere kun svagt takkede og fra 0.056 

 — 0.164— lange og fra 0.020—0.040"™ brede paa Midten, 

 Fig. 52—55. Ind imellem Spindlerne sees Køller, og 

 enkeltvis Klubber, hvilke dog ere mindre udviklede. 

 Køllerne ere takkede, fra 0.124— 0.160'"'" lange og 0.040""" 

 brede foroven, Fig. 56. 57. Klubberne ere sparsomt be- 

 satte med Vorter. 0.104""" lange. 0.032""" brede foroven, 

 Fis. 58. 



Hvad der maa tiltrække sig Opmærksomheden ved 

 Spikelformerne hos Embryonerne, er den Rigclom paa Fir- 

 linger, som tindes hos disse; thi hos det voxne Dyr tindes 

 Firlingerne kun sparsomt og under andre Former, end de 

 hos Larven. Det synes derfor, som om en Hudskiftning 

 her tinder Steel, hvorved Firlingerne blive for Størstedelen 

 udelukkede, medens andre Former indtage deres Plads. 

 En saadan Hudskiftning ved vi jo foregaar hos flere Holo- 

 thurielarver, og Sandsynligheden bliver saameget desto 

 større, naar der tåges Hensyn til, at en stor Del af de 

 øvrige Spikelformer, som tindes hos Larverne, ikke gjen- 

 findes hos det voxne Dyr. Sagtens er det saa, at Spik- 

 lerne uden nogen saadan Hudskiftning undergaa Form- 

 forandringer, alt ettersom Dyret udvikler sig ; men saa- 

 fremt et saadant Forhold existerer, maa man iblandt de 

 lidet udviklede Spikelformer hos den Voxne tinde tilsvarende 

 Former hos Larven, hvilket i Regelen ikke er Tilfældet. 



Farven. 



Stammen, Grenene og Polyperne ere straagule; Ten- 

 taklerne og Mundskiven noget mørkere gule. 



Station. 



Station 275. 

 Station 315. 



Nogle faa Exemplarer. 

 Mange Exemplarer. 



Artskarakter. 



Zoanthodemet indtil 30""» høit. Stammen rund, furet 

 paalangs; dens nederste Trediedel nøgen, den øvrige Del 



The embryons are. already at an early stage, very 

 rich in spicules, and in the' young, liberated from the 

 ovum, the spicular formation is very prominent, so much 

 so, that the spicules lie upon each other, and many and 

 variously formed quadruplets may be observed (fig. 40). 

 Most of them approach to the cruciform, and measure 

 from 0.072 — 0.132""" in length, with a transversal arm 

 measuring from 0.044 — 0.116""" (figs. 41 — 51); only a few 

 approach to the sand-glass form, and these measure 

 0.112""" in length, 0.052""" in breadth towards the 

 extremities, and 0.020""" in breadth at the middle; but 

 more frequent than the quadruplets are, however, the fusees ; 

 these are only faintly spicate, and measnre from 0.056 — 

 0.164'"'" in length, and from 0.020—0.040'"'" in breadth at 

 the middle (figs. 52 — 55). In between the fusees, sub- 

 clavates, and occasionally clavates, are seen; the last are 

 however imperfectly developed. The subclavates are spi- 

 cate, and measure from 0.124 — 0.160""" in length, and 

 0.040""" in breadth above (figs. 56. 57). The clavates are 

 sparingly beset with warts, and measure 0.104""" in length, 

 and 0.032""" in breadth above (fig. 58). 



What must attract attention, with regard to the spi- 

 cular forms in the embryons, is the wealth of quadruplets 

 found in them*, because, in the adult animal quadruplets 

 are only sparingly found and in other forms than those 

 of the larvæ. It appears, therefore, as if a casting of the 

 integumental covering occurs, here, by which the quadrup- 

 lets are, for the greater part, excluded, whilst other forms 

 occupy their place. A. similar casting of the dermal cover- 

 ing, we are already well aware, takes place in several of 

 the larvæ of Holuthurians, and the probability is so much 

 the greater, when it is observed that a large part of the 

 remaining spicular forms found in the larvæ are not, sub- 

 sequently, recognised in the adult animal. It is true 

 enough that the spicules undergo transformations in form, 

 according to the progress of development in the animal, 

 without any casting of the dermal covering, but if such a 

 state of relations exists, we would, amongst the little- 

 developed spicular forms in the adult animal, find corre- 

 sponding forms in the larvæ, and this is, usually, not 

 the case. 



Colour. 



The stem, the branches, and the polyps straw-yellow ; 

 the tentacles, and the oral disk, somewhat darker yellow. 



Habitat. 



Station No. 275. A few specimens. 

 Station No. 315. Numerous specimens. 



Specific characteristics. 



The Zoanthodem measures up to 30 mm in height. 

 The stem cylindrical, longitudinally grooved; its inferior 



