INDEX. 
4,i0 
Patronenstrecke 361. 
Patulous aperture 34. 
Paueisjiiral, univalve ‘26, operculum 126 
Pearls fislierie.s o.Jd, formation 3.24, 
medicinal rei)utation 4-2^ structure 
86, 325. 
rcctcn, pallial eyes 234. 
Pectinibranchiata S. 
Pedal, ganglia 137, 143, J13, ganglion 
cells of Unio picturinn 218, of Aiw- 
(h)uta 168, of Helix I4S, gland 157, 
3.27, mu.scles of Anodonta ISO, 182, 
133, nerves of Vivipara 218, region 
135, 192, retractors in Helix 153, 
lielecyi)oda 347. 
Pelccypoda 9, 36, adductors 345, buccal 
cavity .243, buccal ganglia .210, byssal 
gland 316, mucous lilaments 319, 
pericardial glaml 337, pronephros 
337, retractors 34i>, salivary glands 
34s, structure of shell 37, growth 4'3, 
ne])hridia 333, nervous .system 167, 
215, 217, osphr.adium 3.23, j)allial 
eyes .2.{3, sculpture .^9, torsion 7203, 
visceral ganglia 331. 
Pe/lrr eoroiinto, sperm duct 360. 
Penial plates 363. 
Penis 362, in basommato]ihora 343, 
Helix finpcr.'ia 161, 162, Jl. ni fencoi.^ 
362, Liiiinwei pedustris 362, Planor- 
hi.'i curnciis 366, Snerinen 344-, Vfd- 
ciilti jiitieinali.'s 189, 362, Vieipara 
riri/iiird 189, retractor in 759. 
Pentadroma 285. 
Pentatamia, development and arrange- 
ment of banding 96, formuhe 96, 
geographical distribution 389. 
Peripodial groove 192. 
Perforate univalve 29. 
Pericardial gland l.'/0, 337, Anodunta 
179, function I40. 
Pericardium, Anodoiifacipjiica section 
180 . 
Pei'iostrjicum 21. 
Periostracal appendages 73, 74, 75, 
formation of 74, use of 74- 
I’eriphery 59, carinate 31, rounded 31, 
snbearinate 31. 
Peristome 31, 32, continuous 31, de- 
tached 31, interrupted 32, simple 
32. 
Peritremc (see Peristome). 
I’ervious univalve 29. 
Periodicity 391. 
Phadsm 93, pi. ii., f. 3. 
Phagocytes 396. 
Pharyngeal, retractor 342, in Amalia 
ipajates 342, in Avion suhfuscus 344, 
in Helix a.'ipersa 159, in Lima.v maxi- 
mas 344, Limmca percejra 343. 
Pharynx cells 257. 
Philodromus limacam 423. 
Photoskioptic vision 235. 
I’hylogeny 11, 373, 
Phijsa foniinalis 202, arrangement of 
teeth-rows 262, odontopliore 268, 
odontophoral formula 369, pallial 
outgrowth 202. 
V. inflata .24. 
Pigment cells I40, 173, 337, excretory 
function of 3.27. 
Pillar of shell 29. 
Pilose shell 27. 
Pisidium amnicam, form 40, 53, si- 
phonal tube 200. 
Pisidium fontinalc, form 53. 
Pisidium hensloiranum, prosogyratc 
umbones 110, umbonal appendages 
42, 73. 
Pisidium milium, form 51. 
Pisidium nitidum, form 51. 
Pisidium pusillum, cleavage in egg 
segmentation 378, form 51, morula 
stage 380. 
Pisidium sinuatwm 40. 
Place of origin 336. 
Planorbis, ureter 336. 
Planorbis nlbus, spiral striation of 27. 
V. draparnaudi, hairy ridges of 
shell 74, V. sulcata 23. 
Planorbis carinatus, monstrosities 
from |iit water 104. 
• m. sinisfrorsum 114. 
Planorbis eontortus 26. 
Planorbis corneus, auriform lobe 201, 
304, form 25, male organ 366, nerve 
ring 114, odontopliore 270, odonto- 
phoral formula, 279, osphradium 225, 
periostracal hairs on young 27, 74, 
pronephros 336, respiration 305, 
speed 349, spire 30, variation in 
size 35. 
V. albinn 25, 30. 
Planorbis niarfjinatus, tentacles 189. 
m. roehlca 113, 116. 
Planorbis nauf ileus, dimorphic 70. 
V. crista 27. 
Planorbis siinilis 75. 
Planorbis spirorbis, apertural rib 69, 
epiphragm 131, scalarid 26. 
m. jiriscum 113, 117. 
Planorbis umhilicatus see inarginatus. 
Planorbis vortex m. columella Wl. 
Plants, chemical defences of 233, de- 
fensive devices of 286, structural 
defences of 287. 
Plecton 280, 282. 
Pleistocene deposits 415. 
Pleune 260, 201. 
Pleural ganglia I40, 230. 
Pleurecbolic protru.sion 188. 
Pleurembolic retraction 188. 
Pleurognatha 248, 249, 251. 
Pleuro-pedal connectives 169. 
Plicic of aperture in Claus ilia 67, 68. 
Plicate, aiierture 35, sculpture 27. 
Pliocene, fo.ssils 414> strata 473. 
Pneumonochlamyda 8. 
