INDEX. 
441 
Anodonta ci/(jnca (contd. ). 
mouth 190, muscular system 181, 
347, muscle-scars 10, 55, 180, neph- 
ridial section 179, 334, nervous sys- 
tem 167, 168, 216, olfactory m'gans 
171, orbicular muscles 181, otocysts 
170, 237, otolith 170, pedal ganglia 
168, pericardial gland 179, 180, pro- 
ductiveness 372, ridges of palps 191, 
section, showing nerve-centres 169, 
stomach 172, stomach, section of 171, 
symphynote 41, tactile siphonal ten- 
tacles 244, typhlosole 171, 172, 173, 
venous system 175, ventricle 290, 
visceral ganglia 169, young 41. 
V. cordata 53, v. diminuta 44, 
V. incrassata 79. 
Anodonta Jluviatilis, muscular sys- 
tem 181. 
Annulus of dart. Helix aspersa 366. 
Anterior adductor 182, 343, 347, de- 
velopment of 346. 
Anterior, chamber of bivalves .^.9, crest 
43, gland 314, gut 2^5, margin 37, 
pedal gland 196, 314, pedal re- 
tractors 182, 347, protractors 182, 
salivary glands 275, sinus 44. 
Anteriorly-produced bivalves 40. 
Anteriorly-truncate bivalves 53. 
Antero-lateral hinge-teeth 46. 
Antero-ventral torsion 206. 
Aorta 292, anterior, of Helix 155, of 
Anodonta 174, posterior, of Helix 
155, of Anodonta 175. 
Aperture 31, 32, auriculate 32, com- 
pressed 33, contracted 31, circular 
33, deflected 34, dentate 34, in- 
flected 34, longitudin.al 32, lunate 
33, marginate 35, oblique 33, patu- 
lous 34, plicate 35, pyriform 33, 
reflected 34, rounded 33, sej)tate 35, 
sinuous 34, transverse 33. 
Apex, defined 30. 
Aphallia, dioecia 352, monoccia 354. 
Aplexa hypnoruni, odour from 230. 
Appendages, umbonal 42. 
Appendicula 364. 
Appendiculate jaw 256. 
Appendix 356, 363. 
Aquiferous system 196, 300. 
Area barhata, pallial eyes 234. 
Archetypal mollusk, organization 142. 
Archenteron 381. 
Arctic region 397, 399, pi. v. 
Area of bivalv'es 45. 
Arion, caudal gland 197, 319, semper’s 
organ 190, 243. 
A rion ater, arteries 293, colour changes 
during growth 327, connective tis- 
sue-cells 293, foot fringe 192, mouth 
185, organs of Semper 185, neuro- 
epithelialcell 135, peripodial groove 
192, vision 235. 
v. rufa pi. ii., f. 6. 
Arion cireinnseriptus,fiex\\oX organs 371. 
Arion hortensis 203, alimentary tract 
246, mucous (ilament 317, pallial 
out-growth 203, sexual organs 357. 
Arion suhfuscus, cephalic retractors 
344, mucous filament 317. 
Armature of aperture 66, in young 67, 
Clausilia 68, dentate 34, plicate 35, 
marginate 35, septate 33. 
Arteries 293, Anodonta cygnea 174, 
Arion ater and Testacdla lialio- 
tideu 293. 
Articulate operculum 127. 
Atavism 113. 
Atrium 371. 
Auditory organs 138, 237, of arche- 
type 142, of Anodonta 170, of Helix 
151, canal of 2.38. 
Augury by snails 434- 
Aulacopoda 193. 
Auricle, gland of (see Lymphatic gland) 
Auricles .2.97, Helix aspersa 155, Ano- 
donta 173, 174. 
Auriculate apertui-e 32. 
Auriform a))erture (see Auriculate). 
Auriform lobe, Flanorbis corneus 201, 
304. 
Auri-ventricular valves 174- 
Australasian region 397, 398, pi. v. 
Auxiliary organs 123. 
Azcca tridens, columella lamella 128. 
V. nouletkum 33, aperture 33. 
Azygobranchia, defined 7. 
Bacilli of concretionary gland 339, 
function 339, movements 339. 
Bait 431. 
Balea. perversa, form 24, habitat 85. 
Banding 95, abrupt development 100, 
causes of 96, development 98, disin- 
tegration 99, foi'niulm 96, fusion 
100, rhythmic development 100, 
vestigial 101. 
Basal membrane 260. 
Basal plate 266, 269. 
Base of univalves 30. 
Basommatophora, defined 9, locomo- 
tion 349, nervous system 214, 215, 
otoconia 239, speed 349, ureter 336, 
retractors 343. 
Bathymetrical distribution 390. 
Batrachian enemies 4I8. 
Beak of bivalves 43, 44. 
Beloglossa 267, formula 268. 
Belogonaeuadenia, sexual organs 394, 
distribution pi. iv. 
Belogona siphonadenia, sexual organs 
394, distribution pi. iv. 
Bembridge deposits 412. 
Bibliography 13, 18, 131, 383, 405. 
Biforate pelecypod 165, 198. 
Bilateralia 209. 
Bipolar ganglion cells 210. 
Birds as enemies 417. 
