198 



Trans. Acad. Sci. of St. Louis. 



Lepidocentrus 9, 11, 16-18, 22, 23, 



70 

 Lepidocidaris 11, 72 

 Leptechinus 11, 74 

 Leptosurcula n. gen. 157 

 Limnaea 103 



Lophiotoman. gen. 130, 134 

 Lyrosurculd, u. gen. 156, 157 



Mangelia 165-167 



Megasurcula n. gen. 138, 139, 147, 



148, 151 

 Melechinus 40 

 Melonechinus 40 

 Melonites 2-9, 11, 23, 37, 40-44 pi. 



1-6 

 Microdrillia 127, 138 

 Microsurcula n. gen. 154-156 

 Mitra 161 



Mitromorpha 224, 168-170 

 Mcmiliopsis 138 

 Murex 147 

 Myriastiches 11, 74 



Nesaea 164 



Oligoporus 6, 9, 11, 37-40, iSpl.1-2 

 Oligotoma 148 



Orthosurcula n. gen 144, 151, 152 

 Othake xxxix 171-180 



Palaeohinus 9, 11, 17, 27-37, 41, 42 

 Palaeocidaris 17, 31, 45, 52, 53, 55, 



63 

 Palaeodiscus 10, 12, 13 

 Palafoxia 173, 174, 176, 177 

 Perischocidaris 9, 18, 19 

 Perischodomus 9, 11, 18-20 

 Permocidaris 11, 74 

 Perrona 126 



Philoraycus 101, 102, 105 

 Pholidocidaris 11, 22, 23 

 Pbysa 103 



Planorbis xxxi 107, 108 

 Pleurofusia 127, 152, 153, 156 

 Pleuroliria 128, 130-133, 138, 144 



Pleurotoma 123, 129, 130, 133, 137- 

 139, 147, 148, 150, 151, 155-158, 

 161, 163 



Pleurotoraella 163, 165 



Polygyra 101, 102, 105, 107 



Polypteris 171-174, 176, 177, 179 



Proterocidaris 11, 74 



Protocidaris 11, 75 



Protoechinus 11, 76 



Protosurcula n. gen. 138, 144-146, 

 158 



Pseudotoma 161, 163 



Pyramidula 101, 102, 104 



Raphitoraa 165 

 Rhoechinus 11, 27-30 

 Rouaultia 133 

 Ruscula n. gen. 161, 162 



Scobinella 129, 138-141, 147 

 Sinistrella 138, 139 

 Spatangopsis 11, 75 

 Stevia 171-174 

 Strobilop8 101, 102, 104 

 Strombus 161, 162 

 Surcula 129, 137-139, 148, 151, 152 

 Surculoma n. gen. 153, 154 



Taranis 169 

 Teres 165 

 Tomella 126 

 Tomopleura n. gen. 138 

 Tradescantia xlii 181-193 

 Tretechinus 18, 20 

 Tropisurcula n. gen. 153 

 Trypauotoma 138, 139, 141, 142, 148 

 Turricula 151 

 Typhlechinus 31, 35 

 Typhlomangelia 160 



Varicobela n. gen. 161, 162 

 Vitrea 102, 105 



Xenocidaris 11, 75, 76 



Zelia 138 

 Zonitoides 102, 105 



