EXPLANATION OF PLATES. 395 



68. Xiphoteuthis elongfita, Beche. Lias, England, . . 47 



69. ConoteutMs Dupinianus,d'Orb. Neocomian, France, . 48 



70. Belemnitella mucronata, Sowb. Cret., . . . .47 



71. Trachj'teuthis hastiformis, Riippell. Jurassic, Europe, 44 



72. Belemnites excentricus, Keferstein. Oolite, England. . 46 



73. Clinoceras dens, Mascke. L. Silur., Prussia, . . 53 



74. Acanthoteuthis antiquus, Cunnington. Oxford Clay, 



England, ......... 48 



75-77. Scaptorrhynchus miocenicus, Bellardi. Tert., Pied- 

 mont, .......... 37 



Plate 29. 



78. Orthoceras (Actinoceras ) Richardsoni, Stokes. Pal., 



L. Winnepeg, ......•• 52 



79. Orthoceras subannulare, Barr. Sil., Bohemia, . . 51 



80. Beloptera belemnitoides, Bl. Eocene, France, . . 48 



81. Spirulirostra Bellardii, d'Orb. Tertiary, Turin, . . 48 



82. 83. Tisoa siphpnalis. Marcel de Serres. Jurassic, 



France, 53 



84. Orthoceras (Ormoceras) Bayfieldi, Stokes. Palaeozoic, 



K Am., . 52 



85. Orthoceras (Huronia) vertebralis, Stokes. L. Silurian, 



Lake Huron, . . . . . . • .52 



86. Belemnosis plicata, Edwards. Eocene, England, . . 48 



87. Heliceras Fuegiensis, Dana. Cape Horn, . . .47 



88. 89. Neumayria fulgens, Trautsch, . . . . .79 



90. Strombolituites Torelli, Remele. L. Silur., Germany, 56 



91, 92. Xenodiscus plicatus, Waagen. Carbon., India, . 69 



Plate 30. 



93. Tretoceras bisiphonatum, Salter. Silur., England, . 52 



94, 95. Gonioceras anceps. Hall. L. Silur., U. S., . . 53 



96. Colpoceras virgatum, Hall. L. Silur., New York, . 53 



97. Piloceras (after Salter). Ideal section, . . .54 



98. Cyrtoceras acuticostatum, Sandb., . . . .54 



99. Oncoceras constrictum, Hall. Sil., New York, . . 54 

 100. Gomphoceras pyriforme, Murchison. Silur., England, 54 



1. Gomphoceras Bohemicum, Barr. Silur., Bohemia, . 54 



2. Sycoceras orthogaster, Sandb., . . . . .54 



3. Ascoceras Bohemicum, Barr. Silur., Bohemia, . . 55 



4. Phragmoceras ventricosum, Murchison. Silurian, 



England, 55 



5. Nothoceras Bohemicum, Barr. U. Silur., Bohemia, . 55 



Plate 31. 



6. Phragmoceras cftHistoma, Barr. Silur., Bohemia, . 55 



7. Gyroceras Goldfussii, d'Arch. Devonian, Eifel, . 55 



