243 



Lvogjrus lehnerti (liy) 



Macrocyclis 33 



vancouverensis (34) 

 Macrophysa (100), loi 

 Margarita oregonensis (128) 

 Margaritana 131 



falcata 132 



margaritifcra II, 132 

 Melania 117 



canaliculata (116) 



conica (116) 



plicifera (116) 



silicula (116) 

 Melantho decisa ( 125) 

 Menetus (81), 5-', 86 



exacuous 91 



opercularis 92 

 Merriam, C. Hart, preface v 

 Microphysa 99 



lansingi 44 



pygma;a (53) 



stearnsii (44) 

 Mollusks 1-171 



bibliography 147-153 



fresh water shells, distribution i-6. 

 9-15 



genera and species, systematic dis- 

 cussion 19-145 



land shells, distribution 7-15 



plates and plate descriptions 154, 

 156 

 Mouretia (ill) 

 Muretia (iii) 

 Musculium jayanum 139 



lenticula 140 



partumeium 139 



rayinondi 138 



tenue 139 



transversum 139 



truncatum 140 

 Mya complanata (133) 



margaritifera (132) 



radiata (126) 

 Myxas (104) 



Naiades izs 



Nauta (104) 



hypnorum (106), (107) 



Nauta polaris (107) 

 Nautilina (S3) 

 Nautilus crista {96) 



lacustris 97 

 Neritostoma j5, (61) 

 Nutting, C. C, hydroids 173-234 



Obelia tgi 



borealis 177, 192, 220 



dichotoina 177, /<?/ 



dubia 177, 192, 222 



plicata 177, 191 

 Odostomia (115) 

 Oligolimax (36) 

 Omphalia (61 ) 

 Omphalolimnus (61), 63 

 Omphiscola 60, (61), 62 

 Onchidella 112 



borealis II2, 113, 114 



carpenter! 113 



celtica 112, 113, 114 



floridana 114 

 Onchidiids: 112 

 Onchidium m, 114, 115 



boreale (112) 



celticum 113 



nigricans 112 



Schramm! 114 



typhs 112 

 Orbis (81) 

 Oreohelix 5/ 



cooperi 52 



stactoni %i 



strigosa j /, 52 

 Oxyloma 55 



hungaiica 55 



Pagana (36) 



Paludina cincinnatiensis 118 



decisa (125) 



emarginata (118) 



grana (118) 



hyalina (91) 



limosa (i 17) 



lustrica 120 



nuclea ( 119) 



obtusa (118) 



porata (117) 



seminalis (119) 



