515 



after the most anxious examination of numerous specimens tliat 

 I concluded to unite the various synonyma above enumerated, to 

 the description of tliis species. The British varieties are well 

 known ; of the foreign varieties, var. Heildreichii is found in the 

 Lago di Garda, Italy ; var. zehrina, at Montjjellier ; var. Tolapo- 

 nensis, at Morea; var. numidica, in the " Vallee de Tiri a Oray;" 

 and several varieties are found in Sicily ; var. mittreana is foiuid in 

 France ; var. thermalis in hot springs in the Pyrenees ; var. sardoa 

 is from Sardinia ; and vai". trifasciata in the ditches at Milan. 



27. Neritina transversalis (pi. cxiv. f. 151, 152), Ziegler. 

 Rosmasler, Icon. pi. 7= f. 121. 



N. testa N.flimatili simiU, sed magis ovali; labio interno sub- 

 calloso ; colore coeruleo, trifasciato. 



Of a more sunply oval form, with generally a smaller spire, and 

 the left edge of the inner lip slightly callous. The outer lip does 

 not exliibit the same tendency to spread at the lower part. The 

 colour is ashy, with tliree very obscure dark transverse bands. 

 Operculum of a reddish colour. 



28. Neritina succinea (pi. cxiv. f. 153, 154), Uecluz, Rev. 

 Zool., 1841, p. 343. 



N. testa N. fluviatili simili, sed spira complanata ; colore suc- 

 cineo. 



A minute, amber-coloured shell, of the general form of N. 

 fluviatilis, but with the spire flatter. 

 Guadaloupe. 



29. Neritina meridionalis (pi. cxv. f. 187-190), Philippi, 

 Enum. MoU. Sicil. p. 159, no. 3. pi. ix. f. 13 var. N. inqui- 

 nata, Morelet, var. f. 189. N. lutescens, var. N. Philippii, 

 Recluz, var. N. BcBtica, Lam. Anim. s. Vert. vi. p. 188. N. 

 Moreleti, Recluz. N. elongatula, Morelet. 



N. testa transverse subelongata, Isevi, varie picta vel nigra ; 

 spira exsertiuscula ; apertura senulunari ; labio interno Isevi, com- 

 planata ', labio externo superne subdecHvo. 



Although some specimens of even the British variety of N. 

 fluviatilis approach tliis species in form, yet the prevaihng form 

 of the two are different, this being less elongated, and having the 

 upper part of the outer hp much more sloping. On examining 

 a large number of specimens I fully concur with M. Philippi in 

 uniting several of the above synonyma with this sjiecies ; and I 



