INSTITUTE OF SCIENCE, PHILADELPHIA. 69 



VOLUTOID SERIES. 

 I. Trochiform Type (PI. 6, fig. 3). 

 A. Nucleus small, simple. 

 Cretaceous. Rostelliles navarroensis Shumard, R. Gabbii White {fide Gabb) ; Liopep- 

 lum {Lioderina) liodernia Conrad, L. Spi/hncini Tuomey ; VohUomorpha enfaulensis 

 Conrad. 

 Eocene. Vohitilithes petrosa, Sayana, rugaia and limopsis of Conrad ; V. Haleanus Whit- 

 field. In Europe V. spinosa, bulbula and labrella Lamarck ; V. /uctalor, lima and am- 

 bigna Sowerby ; Lyria harpiUa Lamarck (partly). Lyria sp. ind. (Prairie Creek beds. 

 Lower Eocene, Miss.); L. Edwardsi hrch, non Desh. 

 Miocene. Lyria mississippiensis Conrad, L. piilchella Shy., L. musicina and zebra Heil- 

 prin. In Europe L. cosiaia Sowerby, L. simplex Brocchi, Athleta rarispina and A. 

 ficulina Lamarck. 

 Pliocene. Vohitilithes D' Orbignyana, Doineykoana and gracilis Philippi, V. iriplicata 



Sowerby ; Lyria sp. (Costa Rica). 

 Recent. Voluiilithes Philippiana Dall and, probably, V. ( Voluiocorbis) abyssicola Adams 

 and Reeve ; Lyria sp. (probably nearly all the species) ; Enceta sp. (W. Am.). 

 B. Nucleus small, planorboid, smooth. 

 Eocene. Rare individuals of Volutilithes petrosa and Lyria harpula Lamarck. 



C. Nucleus larger, sculptured, trochoid or planorboid (PI. 6, figs. 7, 8). 

 Pliocene. Valuta musica Linn^, Valuta sp. (Costa Rica). 



Recent. Valuta tmisica, virescens, vespertilio and Narrisii ; without radiating sculpture, 

 V. imdulata,'^ V. reticulata, Elliott and Angasi. 



D. Nucleus of Mela, very large. 

 Recent. Valuta scapka, magnifica, itnperialis ; Mela indicus and all the other species of 



Mela.'^ 



E. Nucleus pupiform. (PI, 6, fig. 3 a). 



Eocene. Valuta cithara, lyra and imisicalis Lamarck. 

 Miocene. Valuta elegans Grateloup. 



2. Bulbous Type (PI. 6, fig. 5 a ; PI. 7. fig- 10). 

 Eocene. Zyrza.^ sp. (Texas Eocene). Valuta Newcoinbiana\\\\\X.fi<i\A. Some specimens 

 of Lyria mississippiensis Conrad and L. harpula Lamarck, though very small, are bul- 

 biform. 

 Miocene. Lyria zebra Heilprin, probably, some specimens. 

 Pliocene. (?) 



Recent. Valuta rupestris Gmelin (typical and large), V. hebrcea and V. vexillum La- 

 marck. 

 * I find the nucleus of this species trochiform and of moderate size, hardly "small" and certainly not 

 " pointed, " as staled by authors. 



t The Cretaceous Melo pyviformis is not a Uelo. The few species referred to Melo from rocks earlier than the 

 quaternary belong elsewhere. The group is not known earlier than the quaternary. 



