60 MOLLUSCA. 



There is one species which is remarkable for a border and stony 

 traverse, on the internal face of its operculum *. 



The organs of respiration in these animals arc arranged as in the 

 Cyclostoma 1 , and like the latter they can live out of water f. 



MELANIA, Lam. 



A thicker shell ; the aperture, higher than it is wide, enlarges oppo- 

 site to the spire ; the columella without plicae or umbilicus ; length of 

 the spire veiy various. 



The Mclanisp inhabit rivers, but are not found in France, the ani- 

 mal has long tcntacula, the eyes being on their external side, and at 

 about the third of their length J. The 



RISSOA, Freminv. ACMEA, Hartm. 



Differs from Mclania, because the two edges of the aperture unite 

 above. The 



MELANOPSIS, Firuss., 



Where the form is nearly that of a Melania, differs from it in a 

 callus on the columella, and in a vestige of an emargination near the 

 bottom of the aperture, which seems to indicate a relation with the 

 Terebrsc of Brugieres||. In the 



PIRENA, Lam., 



We not only find this little sinus below, but likewise a second on 

 the opposite side^f. 



These two subgenera, as well as the Melanise, inhabit the rivers of 

 southern Europe and of all hot countries. 



There are two genera, detached from the Volutse, which, but that 



* The Ilel. ncrilella, List., LXI, 59, copied Blainv., Malac., xxxix, 2. 



f It is from this circumstance that M. de Ferussac has been induced to class 

 thi* submenus \\ith that of the Cyclostoince in an order which he names the Pvl- 

 manea Oju-rmhtlu. Sec the Monograph of this genus by M. Gray, Zool. Journ., 

 \os. ] and 2. 



J Melanif //iia/v (Melanin amantla, Lam.), Chemn., Tab., 134, f. 1218 and 1219 ; 

 from the Isle of France and Madagascar. 



Add, Mel. tnmcata, Lam., Encyclop., pi. 458, f. 3, a b ; Mel. coarcltt/a, Id., 

 Kitcyclop., pi. 458, f. 5, a b., and a great many fos.sil species, among which are, 

 ^ffl. semi-phicata, Defr. ; Mel. Cucieri, Desh., Coq. Foss., des environs de Paris, 

 tome II, pi. xii, f . 1 , 2 ; Mel. constellafa, Lam. 



M. de Freminville describes seven species in the Nouv. Bullet, des Sc. 

 Nat. de la Soc. Phil., 1814, p. 7, and M. Audouin, three, in the Descr. de 1'Eg. ; 

 /iiss. Fi-uniiii-illii, Coq., pi. Hi, f. 20; Riss. Desmarustii, Ib., 21 ; Rifs. Orbignii, 

 lb., f. '22. 



|| Mchin. Inn-ciiid't'ilcd, Frruss., Mem. de la Soc. d'Hist. Nat. de Paris, tome 1, pi. 

 vu, f. 1 11, &c. .See Sowerby, No. XXII. 



^j Pir. tcnhntlis, Lam.; List. Tab. 115, f. 10; 7V. Htaihtyascarieitsix, Encycl., 

 pi. 458, f. 2, , b, &c. 



