80 Moll. 
MOLLUSCA. 
at Roscoff ; he comes to the conclusion that it respires water as well as 
air, water by the dorsal tubercles, which are very rich in blood-vessels, 
the animal remainiug often for several days below the surface, air by the 
so-called pulmonary cavity, which by its situation, connection, structure, 
histology, and secretion is really homologous to the renal organ of 
other Mollusca. The disposition of the circulatory organs agrees rather 
with that in the Opisthobranchia ; the eyes are placed at the tips of eye- 
stalks as in the terrestrial Pulmonata ; the jaw and radula agree with those 
of some of the Pulmonata ; concerning the development, he states that it 
is provided in the larval stage with an embryonal shell and with a large 
velum, just as in the Opisthobranchia. Arch. Z. expdr. x. pp. 225-283, 
pis. xiv.-xxii. 
Onchidium. C. Semper continues and finishes his review of this genus, 
describing the following new species: — 0. steenstrupi , Nicobars, Caro- 
lines, New Guinea, aberrans , Singapore ?, samarense , Philippines, multi- 
radiatum and trapezoicleum, localities unknown, dcemeli , Sydney, coria- 
ceum , Singapore, Pinang, Philippines, Brisbane, graniferum, Philippines, 
luteum, Singapore, palaense, Palau Islands, papuanum, New Guinea, ovale , 
locality unknown, reticulatum, New Zealand and Sydney, steindachneri, 
Galapagos ; he also gives descriptions of 0. carpenteri (Binn.), California, 
boreale (Dali), Sitkha, celticum (Cuv.), Cornwall, and cinereum (Q. & G.), 
Tongatabu, and critical observations on other described species. Reis. 
Arch. Phil. iii. pt. G, pp. 2G5-28G, figures of the radula and genital organs, 
pi. xxi. figs. 1-2G. 
Onchidina , g. n. Pulmonary orifice rather lateral, right hand of the 
vent ; no penis gland, male orifice behind the right tentacle. 0. australis 
(Gray MS., Onchidella ), Brisbane, Fiji Islands, and Coast of Eastern 
Africa, anatomically described by Sompor, l. c. pp 287-289, radula, pi. xxi. 
fig. 27. 
Onchidella patelloides (Q. & G.). No jaw, median tooth of the radula 
tricuspid, lateral unicuspid, with projecting basal process. Button, Tr. 
N. Z. Inst. xiv. p. 155, pi. iv. figs, u & R. 
Auric ulida5. 
The internal walls of the whorls are completely reabsorbed in Melam- 
2 )us , Auricula , Blauneria, Marinula, Tralia, Alexia, Monica, and Pleco- 
trema, partially and chiefly near the columella in Cassulula and Scarabus, 
not at all in Pedipes ; Crosse & Fischer, J. de Conch, xxx. pp. 177-181, 
pi. viii. figs. 1-14. 
Carycliium biondii , sp. n., Sardinia, and maria \ (Paulucci), Upper 
Italy, Paulucci, Bull. Soc. mal. Ital. viii. pp. 305 & 306, pi. viii. figs. 7 
& 8 . 
Pytliia (Bolten) — Scarabus (Montf.). J. C. Cox enumerates 52 de- 
scribed species of this genus, 4 more than Pfeiffer in his last revision 
(187G), with synonymy and geographical distribution, and critical remarks 
concerning some of them ; J. Linn. Soc. N. S. W. vi. pp. 587-G21. 
[ Auriculastra ] Auricula nevillii , Mauritius, and gassiesi , Mayotte, 
