ECHINODERMATA.
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only different ages of Ophiolepis ciliata, and have recognisedin Ophiomyxa lubrica, Forb., their Ophiomyxa pentagona;in Amphiura neglecta and Chiajii, Forb., their Ophiolepis squa-mata and filiformis; as well as in Goniaster abbensis, Forb.their Astrogonium phrygianum. Muller and Troschel are alsoinduced to unite the genera Ophiothrix and Ophionyx, sincenot only the latter is furnished with many-toothed hookletsbeneath the rows of spines of the rays, but these organs alsooccur in Ophiothrix, though with this difference, that thelatter Ophiuridan presents these hooklets only at the ex-tremity of the rays, whilst in the former they are placedalong their whole length.
The development of the Asteridse has been described bySars (Archiv , 1844, Bd. i, p. 169; or Annales d. Sc. Nat.t. ii, 1844, p. 190), whose observations were made on theova of two new Starfishes, viz. Echinaster sanguinolentus andAsteracanthion Mulleri. The ova lie upon the surface of theabdomen, which is hollowed out so as to constitute a mar-supial pouch. The Echinaster sanguinolentus of Sars is more-over, according to Muller (ib. 1844, Bd. i, p. 169), the Echi-naster Sarsii described by himself and Troschel .
Muller (ib. 1843, Bd. i, p. 131) has described two newComatulse as Alecto purpurea and Wahlbergii, and has sup-posed that the Echinodermata described by Retzius asAsterias multiradiata and pectinata, and preserved at Lund,probably belong to the Crinoidal genus Actinometra in-stituted by him. The Comatulse, but very briefly noticedby Lamarck , have been more particularly described byTroschel (ib. p. 135) from the original specimens, as, Alectocarinata, Adeonee, Solaris, brachiolata, rotalaria, and fimbriata.Muller has given a very important memoir on the structureof Pentacrinus caput Medusa . (Abhandlungen der Akademieder Wissenschaften zu Berlin, a. d. I. 1841 ; Berlin, 1843,p. 177.) He had obtained a specimen from the West Indies ,which, after a preliminary historical review of the researcheshitherto instituted respecting the Crinoidese and Pentacrinus,is described with the greatest particularity. The stem in