GASTROPODA (CTCLOBRANCHIA, TECT1BRANCHIA) . Moll. 55 
found in Patella. He discusses the gills of Chiton , and states that 
their arrangement exhibits two different types ; in one, exemplified by 
C. siculus , they reach nearly along the whole side of the body, and their 
number is thirty-two on each side ; in the other, exemplified by C. Icevis 
(Penn.), they begin considerably more behind, and their number is only 
fourteen. Each leaflet of the gills is itself composed of laminae, number- 
ing twenty-three in the larger gills of C. siculus and fascicularis ; each 
single leaflet is, therefore, homologous to a whole gill of other Mollusca. 
Arb. z. Inst. Wien, v. pt. t, 32 pp., 3 pis. ; abstracts in J. R.Micr. Soc. 
(2) iii. pp. 38-40, 495, & 496, and in Arch. Z. exper. (2) i. pp. xiv.-xvi. 
J. van Bemmelen, Zool. Anz. 1883, pp. 361-3G5, observes that the 
number of the gills in the Chitonidce varies from fourteen to seventy-five, 
and their number is not always in proportion to the relative length of the 
whole row of them along the sides of the animal. A microscopical 
examination of decaleified shells of the Chitonidce leads to the conclusion 
that only the articulamenta, or lower colourless layers, are homologous to 
the shells of other Mollusca , and that the tegmentum, or upper sculptured 
layer, of the shells of Chiton , however calcareous, belongs to a cuticular 
formation, and is homologous to the cuticula of Neomenia. 
Chiton Icevis (Penn.) at Trieste ; Haller, l. c. p. 21. 
Chiton pellis-serpentis (Q. & G.) and glaucus (Gray). Dentition ; Hut- 
ton, Tr. N. Z. Inst. xv. p. 129, pi. xvi. figs, i & f. 
Chiton inornatus , sp. n., Tenison-Woods, Tr. R. Soc. Yict. xvii. p. 82, 
figs. 8 & 9, Victoria. 
Acanthochites zealandicus (Q. & G.). Dentition ; Hutton, l. c. p. 129, 
pi. xvi. fig. g. 
Cryptoconchus porosus (Burrow). Dentition ; id. ibid. pi. xvi. fig. h. 
TE C TIBRANOEIA . 
ACT2EON1D.®. 
Actceon turritas, St. Thomas, 390 fath., amabilis, West of Azores and 
off Palma, Canaries, 1000 and 1125 fath., austrinus , Bass’s Strait, 38-40 
fatli., A. ( Actceonina ) edentulus, Kerguelen, 60 fath., and chariis, Azores, 
1000 fath., A. ( Buccinulus ) cinereus , Fiji, 12 fath., spp. nn., Watson, 
J. L. S. xvii. pp. 284-289. 
Ringicula. The 3 recent species of the Mediterranean, auriculata 
(Menard), conforniis (Monterosato), and leptochila (Brugnone), with seve- 
ral Tertiary species, described, and the 2 former figured, by Seguenza, 
Atti Acc. Rom. Mem. ix. pp. 344-390, 2 pis. 
Ringicula pusilla and assularum, Torres Straits, pcracuta , St. Thomas 
and off Bermudas, 390, 1073, & 350 fath., spp. nn., Watson, J. L. S. xvii. 
pp. 290-292. 
Bulljdje. 
Cylichna discus , St. Thomas, 390 fath., noronyensis , Fernando de No- 
ronha, 25 fath., tahitensis, Tahiti, crispula, Torres Straits, 155 fath., reti- 
