224 INVERTEBRATE PALAEONTOLOGY 



Reptilia, 104, 112 

 Retardation, 106 

 Reteocrinus, 138 

 Retepora, 202 

 Rhabdoceras, 103, 191 

 Rhaetic, 86, 174 

 RhizocrinuS) 180 

 Rhodocrinus t 162 

 Rhombifera, 134, 160 

 Rhombopteria, 145 

 Rhynchonella,) 72, 185 

 Rhynchonellacea, 31 

 Rhynchonellidae, 143, 165, 185 

 Richthofenia, 105, 165 

 Rimella, 206 

 Ripple-marks, 48 

 Rudistacea, 189 

 Rugose Corals, 130 

 Russia, 21 

 Rustella, 141 



Saccammina, 30, 127, 158 



Saccocoma, 179 



Salenia, 182 



Saltations, 75 



Sand, 17 



Sand-dollars, 88 



Sanguinolites, 167 



Sao, 151 



Scalana, 190, 206 



Scalp ellum, 194 



S cap kites, 103, 193 



Scaphopoda, 190 



Schist, 21, 26, 119 



Schizaster, 202 



Schizocystis, 135 



Schizodonta, 145, 167, 187, 204 



Schizodus, 167, 1 88 



Schizophoria, 164 



Schizostoma, 168 



Schloenbachia, 193 



Sclerosis, 106, 117 



Scorpionida, 83, 153, 172 



Scotland, 124 



Scutella, 20 1 



Scutellina, 201 



Sea-Urchins, 16, 19 



Second-childhood, 104, 117 



Sedgwick, 74 



Sedimentary rocks, 27 



Selenite, 19, 46 



Senescence, 105 



Senonian, 88 



Sepioidea, in, 194 

 Septa, 103 

 Septaria, 36 

 Seraphs, 207 

 Serial-sections, 63 

 Sewers, 23 

 Shale, 1 8, 27 

 Shell-marl, 84 



sand, 17, 35 

 Shellac, 67 

 Shells, 13 

 Shelter, 101 

 Sheppey, Isle of, 208 

 Ship-worms, 48 

 Shropshire, 27, 33, 43, 85 

 Sieves, 61 



Silica, 14, 29, 36, 44 

 Silicispongiae, 128, 177 

 Silurian, 28, 125 

 Siphonia, 177 

 Sismondia, 201 

 Skeletons, 13 

 Slaty-cleavage, 26 

 Slimonia, 172 

 Slugs, 82, 207 

 Smith, W., 73 

 Snails, 82 

 Solarium, 190 

 Solenhofen, 49, 194 

 Solenopsidae, 187 

 Sparth Bottoms, 172 

 Spatangidae, 95 

 Spatangoida, 183 

 Spatangus, 202 

 Specialists, 70 

 Specialization, 100 



deferred, 112 

 Sphaera, 190 

 Sphaerexochus, 152 

 Sphaeroceras, 192 

 Sphaeroidothyris , 72 

 Sphaeronis, 135 

 Sphaerospongia, 129 

 Spirifer, 166 



Spiriferacea, 107, in, 118, 143 

 Spiriferina, 186 

 Spirula, 208 

 Spisula, 205 



Spondylus, 40, 105, 189, 204 

 Sponges, 14, 30, 37, 44, 87 

 Spumellaria, 128 

 Stages in ontogeny, 96 

 Stains, 65 



