LIST OF ILLUSTRATIONS xxix 



FIG. l'\i:K 



569. Chiton, nephridial and genital systems . . . . (id'.) 



570. ,, development ... 670 



571. Triton iiodiferus, shell . .672 



572. Triton iiodiferus, shell, median section . . 673 



573. ,, ,, operculum . 674 



574. ,, ,, lateral view of body . . 674 



575. ,, ,, diagram of introvert . . . 675 



576. ,, ,, dissection from dorsal side . . 677 



577. ,, ,, buccalmass .... . . 678 



578. ,, ,, vertical section of buccal cavity .... 678 



579. , , , , nervous system from dorsal side . . . 680 



580. ,, ,, ,, ,, and related parts, lateral view . 681 



581. ,, ,, section of eye . ... . 682 



582. Solarium perspectivum . . . . 685 



583. Terebra oculata . . . 686 



584. Cyprasa nioneta 687 



585. Doris tuberculata . . 687 



586. Carinaria mediterranea ... ... . 687 



587. Limax . . .687 



588. Sigaretus Itevigatus . . . 688 

 589 Aplysia .... . 688 



590. Shell-bearing Pteropoda . . 689 



591. Atlanta peronii .... . . 689 



592. Pterotrachea scutata ... . 690 



593. Helix nemoralis . . 690 



594. Pleurophyllidia lineata . . 691 



595. Patella vulgata ... .691 



596. Pulmonary cavity and related parts in Limax . . . 692 



597. Nervous system of Patella . . . . 693 



598. Diagrams of displacement of mantle-cavity, &c. . . . 694 



599. Nervous system of Aplysia . 695 



600. ,, ,, ,, Limmeus . . . . 695 



601. Eyes of Gastropoda . . 696 



602. Osphradium of Murex . . 696 



603. Reproductive organs of Helix 697 



604. Hermaphrodite gland of Gastropoda . . 698 



605. Forms of egg-cases in Gastropoda . . . 699 



606. Segmentation and formation of germinal layers in Gastropoda . 700 



607. Early development of Patella . 701 



608. Trochospheres of Patella . 702 



609. Later trochosphere of Patella . ... 703 



610. Veliger of Vermetus . .704 



611. Diagram illustrating the relationships of the Gastropoda . 705 



612. Dentalium, section of shell . . 706 



613. ,, anatomy . . . 706 



614. ,, larva* . . 706 

 614/>/,s. Rhodope . . 707 



615. Sepia cultrata . . 709 



616. sucker 710 



