566 
ZOOLOGICAL LITERATURE. 
7 imsiSf J. Miill., and M. australis, sp. n., Semper, /. c. p. 233, Australia. This 
species resembles JELaplodactyla in the form of its body. 
Echinosmna, Semper, = Ltitken. The species described as Ech. 
hispidum, Semp.,=^^^^p. scaber, Lut. j but Lutken’s Eupyrgus, sp. n., belong;s 
not to this genus, is not identical with Eup, hispidus, Barrett, and belongs 
apparently to Sars’s genus Echinocucumis. This necessitates the doing away 
with the family 2, Eupyrgidm, from the Apneumona, as Eupyrgus scaler, 
Liit., belongs to the Molpadidae. 
Apneumona. 
Chirodota, Semper suspects (/. c. p. 231) that C. tig ilium and C. typica of 
Selenka are only varieties of C. pellucida or C. Icevis. 
Sxjnapta petersi, sp. n., Semper, 1. c. Nachtrage, p. 230, Amboina. 
Synapta agassizii, Sel., is placed by Semper as a variety of S. leselii, Jager. 
L. c. Nachtrage, p. 230. 
Synapta kcferstemii, Sel. Semper describes (1. c. p. 230) the biscuit-shaped 
bodies, quite overlooked before by both Selenka and himself. 
Synapta godeffroyi, sp. n.. Semper, 1. c. p. 231, Samoa Island. 
Synapta hispida, sp. n., Heller, 1. c. p. 71, Taf. 3. figs. 6 & 6, Lesina. Near S. 
digitata, Mont. 
Synapta inkcerens and S. sarniensis. Ray Lankester mentions that an im- 
portant distinctive character is to be met w'ith in the miliary spicules, espe- 
cially those of the tentacles of these species, those in S. sarniensis being simple, 
while those in S. inhcerejis ar^ much branched. Quart. Journ. Micr. Science, 
vol. xvi. p. 54. 
.j Diplostomoidea. 
RhopalodimdcB. 
Rhopalodina layeniformis, Gray. Semper (/. c. p. 252) gives, 
as a supplement to his work on the Ilolothurioidea, a pretty full 
account of the anatomy of this remarkable creature, which he 
places in a separate division of the Echinodermata. The body 
is lageniform; in the hinder portion are ten ambulacra, and, 
corresponding to these internally, ten radiating muscles, ten 
ambulacral canals with ampullse, and ten nerves; these ten 
rays are prolonged into the peduncle, but bear no feet ; at the 
free extremity of the peduncle are the mouth and anal opening, 
sido. by side ; the oral margin is entire ; anal margin with ten pa- 
pillae. The pharynx and terminal portion of the intestine travel 
side by side in the interior of the peduncle. The stomach forms 
a spiral with numerous turns and a double loop. Of the ten 
rays, five correspond with the pharynx and five with the intestine. 
There is a calcareous pharyngeal ring formed of ten pieces, and 
a calcareous anal ring of like number. 
In all living Echinoderms the anus is placed either opposite 
to the mouth in the centre of the radiate arrangement or in an 
interradium. In the Crinoidea tessellata there exist more than 
five rays placed round a single central aperture ; but with this 
section Rfiopaludina has little else in common. 
