ZOOLddldAt LITERAtURE. 
6 ^^ 
OPHIUMDEA. 
Norman', A.M. On tlie Morphology of the Ophiuroidea, Rep. 
Brit. Assoc. Newcastle, 1863, Trans, of the Sections (p. 106). 
A short abstract. 
Norman thinks that certain points in the skeleton of the 
Ophiuridea, hitherto little noticed, will be found valuable in the 
discrimination of species. These, we presume, he will indicate 
in a future paper. He enumerates six species new to the British 
fauna, namely : — 
Ophiura sarsii (Liitken) j O. squamosa (Liitk.) j O. affinis (Liitk. ; syn. of 
O. normanni, Hodge) ; Amphiura chiajii (Forbes) ; OpMopeltis securigera 
(Diiben & Koren) j Asteronyx loveni (M. & T.). 
Grube notices Ophiopsila aranea (Heller), Ophiura albida (Forbes), and 
Ophiodenna longicauda (M. & T.), besides citing five other species of this 
order from Lossiui. 
ASTERIDEA. 
Aoassiz, a. On the Embryology of Asteracanthion berylinus 
Ag. and a species allied to A. ruhens M. T. A. pallidusy 
Ag. Proc. Amer. Acad. April 14, 1863 (pp. 1-8, with a 
folding plate). 
Saks, M. Om en ny Art Brachiolaria. Eorhandliuger i Viden- 
skabs-Selskabet i Christiania, Aar 1863 (pp. 126-137). 
Agassiz describes the early development of the ‘Marva^^ of 
Asteracanthion berylinus, which he raised from the egg by means 
of artificial fecundation. He observed the disappearance of the 
germ-vesicle and germ-spot, the subsequent segmentation of the 
ovum, the formation of the blastoderm, of the alimentary canal, 
and of the ambulacral- vascular rudiments. The alimentary canal 
commences as a diverticulum inwards, the first-formed opening 
of which eventually becomes the anus, though for a time it acts 
the part both of an ingestive and egestive orifice. This diverti- 
culum lengthens, till, reaching the opposite pole, it joins the oral 
depression. The entire canal now divides into gullet, stomach, 
and intestine. 
While yet the alimentary canal is but half the length of the 
larva, the ambulacral rudiments appear as two small pouches 
developed laterally from its inner, Ccecal extremity. They soon 
become hollow bodies, quite distinct from the digestive cavity 
and from one another. Hence these larvae would probably have 
assumed the brachiolarian type, whose evolution our author was 
enabled to trace in the case of A. palUdus. His observations on 
this species well serve to complete those on A. berylinus, as they 
commenced with specimens in which the two distinct rudiments 
