146 Zoological Society. 



Remarks. — The markings are very variable, being sometimes ob- 

 lique, zigzag lines, extending over the whole surface of the whorls, 

 sometimes sagittate or short zigzag spots in transverse series. Indeed 

 some specimens are of a uniform dark green. The last whorl some- 

 times has two impressed transverse lines. The mouth is nearly two- 

 thirds the length of the shell. 



Melania polygonata. M. testd tuberculatd, elevato-conicd, 

 slriatd, crassd, nigra ; spird elevatd, conicd, apice erosd ; suturd 

 peene obsoletd, fiexuosd ; anfractibus superne et in/erne striatis ; 

 medio anyulatis ; angulo serie unicd tuber culorum instructo ; tu- 

 berculis maximis, transverse angulatis, Icevibus ; striis transversis 

 raris ; anfractu ultimo magno ; basi crebre slriatd ; aperturd su- 

 perne valde acutd, in/erne productd et effusd, intus albidd ; colu- 

 melld albd, fiexuosd ; operculo parvo, subcentrali. 

 Hab. Copan, Central America. 

 Length 3*5, diam. 1*3 inch. 



Remarks. — One of the largest and finest of the Melanice. The 

 upper whorls are generally covered with a thick, smooth deposit, 

 obliterating the sculpture. On them the tubercles appear to dege- 

 nerate into elevated costse. The operculum is much smaller than the 

 mouth. The tubercles and striae sometimes produce brown marks 

 on the columella and inside the aperture. 



Melania denticulata. M. testd spinosd, ov at o -turrit d, trans- 

 versim striatd, denticulatd, tenui, diaphand ', ferrugined, maculis ba- 

 diis minutis linearibus ; spird exsertd, conicd, scalariformi, apice 

 acuminatd ; suturd lineari ; anfractibus septem, superne angulatis, 

 angulo denticulatis ; denticulis parvis , acutis, obliquis; striis trans- 

 versis, parvis, alternanlibus, rugosis, maculatis, lineolis longitu- 

 dinalibus minutissimis decussatis ; anfractu ultimo parvo, ad basim 

 striato ; aperturd ovatd, inf erne effusd; columelld fiexuosd, tenui. 



Hab. Mountain streams, isle of Negros, Philippines. 



Length "6, diam. *3 of an inch. 



Remarks. — Allied to M. spinulosa, Lam., but may be distinguished 

 by its abrupt denticulations. 



Melania armillata. M. testd cancellatd, ovato-turritd, cras- 

 siusculd, graniferd, viridescenti ; spird elevatd, subovatd, apice 

 acutd; suturd parvd, crenatd ; anfractibus undecim, planatis, 

 prope suturam superiorem angulatis, superne albidis, costis longi- 

 tudinalibus obliquis graniferis crebris ; granulis rotundatis, albi- 

 dis ; anfractu ultimo superne compresso, inf erne subturgido ; basi 

 transverse striatd; aperturd ovatd, superne acute angulatd, in- 

 ferne rotundatd, et effusd ; labro inf erne produclo ; columelld in- 

 ferne angulatd, superne rectd. 

 Hab. India. 



Length 1*4, diam. *5 inch. 



Remarks. — Immediately below the angle of the whorls there is 

 apt to be a larger series of granules, with a very small one succeed- 

 ing it. 





