91 
Case 10, — Spondylidae continued; Ostreidae (Oysters); Den- 
taliidae (toothed-shells) ; Chitonidae{Oci\\.on^) ; Patellidae (Limpet 
Shells.) 
Case 11, — Patellidae continued; (Keyhole Lim- 
pets) ; Haliotidae (Ear Shells Ablone) ; Trochidae. 
Case 12, — Trochidae continued; Turbinidae (Top Shells), 
Neritidae. 
Case 13. — continued; Naticidae ; Xenophoridae. 
Case \4.—Calyptraeidae (Limpets); Ampullariidae {Apple 
Snails) Littorinidae (Periwinkles.) 
Case 15. — Melaniidae ; Turritellidae ; Vermetidae (Worm 
Shells, the shells being more or less contorted like worm tubes), 
Cerithidae. 
Case 16. — Strombidae (Conch Shells) ; Cypraeidae (Cowries), 
a family containing some of the most beautiful shells known. 
Case 17. — Doliidae (Tun Shells) ; Cassidae (Helmet Shells) ; 
Tritonidae (Triton Shells.) 
Case 18. — Tritoniadae continued; Muricidae, a large family 
of mostly spiny and roughened shells. 
Case \9.—Muricidae continued; Nassidse (Dog Welks) ; 
Bucinidae (Welks) Turbine llidae. 
Case 20. — Turbinellidae continued; Fasciolaridae ; Fusidae 
(Spindle Shells); Mitridae (Mitre Shells.) 
Case 21. — Volutidae, a family containing many large and 
beautifully colored shells; Marginellida ; Harpidae (Harp Shells.) 
Case 22. — Olividae (Olive Shells); Conidae (Cones), an ex- 
tensive family living mostly in warm seas. 
Case 23. — Conidae continued. 
Case 24. — Teribridae (Augur Shells); Bullidae. 
Case 25. — Materials illustrating two groups of mollusks, 
many of whose members have the shell rudimentary or wanting 
entirely. Many of these animals are represented here by beauti- 
fully executed glass models ; Limnaeidae, 
Case 26. — Stenogyridae. — This family and the remaining 
ones, which belong to the order Pulmonata, are air-breathing 
mollusks, the largest belonging to the genus Achatina. Most of 
the species live in Africa where they remain in trees, descending 
to lay their eggs. Some of the eggs are exhibited. Pupidae. 
Case 27, — Pupidae eoniimied.’, Bulimidae. 
Cases 28, 29 and 30.—/Telicidae (Air Breathers), a large 
