GASTEROPODA. 131 



MELANIA, Lam. 



Etym., Melania, blackness (from melas). 



Type, M. amarula. PL VIII., fig. 25. 



Syn. Thiara, Megerle. Pyrgula, Crist. 



Shell turreted, apex acute (unless eroded) ; whirls ornamented with striae 

 or spines ; aperture oval, pointed above ; outer lip sharp, sinuous ; operculum 

 subspiral. PL VIII., fig. 25*. 



Distr., 160 sp. S. Europe, India, Philippines, Pacific Islands. Distinct 

 groups in the southern states of N. America. 



Fossil, 25 sp. Eocene. Europe (v. chemnitzia). 



Sub-genera. Melanatria, Bowdich. M. fluminea* PL VIII., fig. 26. 

 Aperture somewhat produced in front ; operculum with rather numerous 

 whirls. This section includes some of the largest sp. of the genus, and is well 

 typified by the fossil, M. Sowerbii (cerit. melanoides, Sby.) of the Woolwich 

 sands. Old World, India, Philippines. 



Tibex, Oken, V. fuscatus, PL VIII., fig. 29. V. auritus. W. Africa. 

 Whirls spirally ridged, or muricated ; aperture broadly channelled in front. 



Ceriphasia, Sw., C. sulcata. N. America. Aperture like vibex ; slightly 

 notched near the suture. 



Hemisinus, Sw., H. lineolatus. W. Indies. Aperture channelled in 

 front. 



Melafusus, Sw. (Io 3 Lea. Glottella, Gray.) M. fluviatilis. PL VIII., 

 fig. 27. IT. States. Aperture produced into a spout in front. 



Melatoma, Anthony (not Sw.) M. altilis. Shell like anculotus ; with a 

 deep slit at the suture. U. States. 



Anculotus, Say. A. prsemorsus. PL VIII., fig. 28. Shell globular; 

 spire very short ; outer lip produced. TJ. States. 



Amnicola, Anthony. A. isogona. PL IX., fig. 23. U. States. 



? Pachystoma, Gray. M. marginata, Eocene. Paris. Peristome thick- 

 ened externally, all round. 



PALUDOMUS, Swainson. 



Etym., palus, a marsh, and domus, home. 



Syn., tanalia, Gray. Hemimitra, Sw. 



Type, P. aculeatus, Gm. sp. PL IX., fig. 34. 



Shell, turbinated, smooth or muricated; with wavy stains beneath the 

 olive epidermis ; spire small, usually eroded ; operc. horny, lamellar, nucleus 

 external. Animal like melania ; mantle-margin fringed (Eydoux). 



Distr., 10 sp. Ceylon (Himalaya?) in the mountain-streams, sometimes 

 at an elevation of 6,000 feet. The Himalayan sp. (melania conica, Gray, 



* This is a good section of melania, but Mr. Gray's type does not well represent it, 

 being more like a pirena in the form of its aperture. 



