Videnskabelige meddelelser

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Videnskabelige meddelelser

149

low in the point and the whole vibratile band is of a faint yellow-

ish tint.

It is perhaps possible to find out to which Asteroid this larva

belongs. The Asteroids occurring in the neigbourhood of the Stat-

ion are the following: Astropecten irregiilaris, Liiiclia Sarsi, Hipp-

asteria phrygiana, Porania pul-

villas, Solaster papposiis, S. endeca,

Henricia sanguinolenla, Stichaster

rosens, Asterias Muller i, glacialis

and rubens. Of these are at once

out of question: the three Asterias

species, Henricia, the two Solaster

species, Porania and Luidia. Hipp-

asleria has large and yolk- laden

eggs, so that it can be said with

certainty that it has no true Bipin-

naria larva. There are thus left

only Astropecten irregularis and

Stichaster roseus. So far as evid-

ence goes the Astropecten larva

belongs to the type of Bipinnariæ

with quite short, not contractile pro-

cesses. (I have tried to rear the larva but never succeeded in

getting suitable material for fertilization). There would then ap-

pear to be no other alternative than that we have here the

larva of Stichaster roseus. My efforts to try to rear the

larva of this species from the egg were in vain/) as I could never

get sufficient material of the species, only now and then a single

specimen. But at any rate I could ascertain that it has its breed-

ing season at this time (August).

Although thus everything seems to point towards Stichaster

roseus as the parent species of this larva, nothing definitely can

be said about it at present. The rearing of the Astropecten irre-

gularis larva would also settle this question.

Fig .3. Bipinnaria of Stichaster

roseus (?) ^/i.

S James F. Gemmill has succeeded in rearing the larva from the egg

till the young Bipinnaria stage. 'Notes on the development of the star-

fishes Asterias glacialis O. F. M. ; Cribrella oculatu (Linck) Forbes

Solaster endeca Retzius Forbes; Stichaster roseus (O. F. M.) Sars.

Proc. Zool. Soc. London 1916. p. 562.

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