159 
raliter maculis oblongo-conicis subserialibus pictd ; apice lateraliter 
compresso, supra fornicato, roseo-purpurascente recto, marginali ; 
labio angusto-triangulari, medio concavo-emarginato, lateribus an- 
tice prolongatis. 
Var. B. T. ellipticd, postice angustatd, luted medio dorsi lineis ni- 
gris angusiis et latiusculis, et lineolis obliquis creberrimis radiis 
latioribus lateraliter efformantibus interdum confluentibus pictd, 
labio triangulari anticé arcuato. 
Var. y. T. oblongd, postic? angustd, subacutd, luted radiis angustis 
nigris medio dorsi notatd, antic? et lateraliter crebre nigrescente 
lineolatd, et maculis linearibus luteis subseriatis pictd ; apice sub- 
violascente ; labio triangulari, antic? arcuatim excavato. 
Var. 5. T. elongatd, lateribus compressa, dorso convexo-fornicatd, 
antic2 subacuto, interdum truncaio ; luteo-fuscescente, maculis ob- 
longis antic? nigris acutis lateraliter lineolis tenuissimis obsoletis- 
que obumbratis picté ; apice interdum nigrescente, labio triangu- 
lari, luteo-fuscescente. ; 
Var. e. T. oblongo-ellipticd, lateribus compressa, lineolis pallide 
fuscis aut purpurascentibus, et maculis oblongo-conicis luteis picta ; 
radiis binis, pallide luteis in medio dorsi notatd ; labio triangularé, 
antice arcuato. j 
Var..a: long. 0°88 ad 1°08; lat. 0°44 ad 0°56; conv. 0°24 ad 0°48 
poll. Var. @ andy: long. 0:96 ad 1-04; lat. 0°60 ad 0°64; conv. 
0°32 ad 0°36. Var. é: long. 0°52 ad 0°64; lat. 0°32; conv. 0°28 
ad 0°32, 
Hab. Var. a, from Banguey, province of North Ylocos: on stones 
in a mountain-stream. Var. 6, from Cagayan: on stones in a large 
river. Var. 6, from Baccara: on stones in a rapid river. Var. e.?, 
cum precedenti. 
All these varieties are very remarkable, and, with the exception 
of var. e, whose operculum I have not seen, all certainly belong to 
the same species. The operculum of Nav. lineata is oblong, very 
thin, pale yellow, a little inclined to pale green, rounded behind, 
notched before, notch in an oblique line at the base. The left side 
of this operculum is slightly arcuated in the centre; the right side 
almost rectilinear and limited by an apophysary tooth, very narrow 
and a little prolonged anteriorly. Muscular impression triangular, 
elongated, inclined obliquely to the left. 
9. Navicetta Entrecasrauxi, Récluz. Rev. Cuvier, p. 380, 
No. 14. 
Var. 2. T. obovatd, nigro-purpurascente, concentrice et crebre lineo- 
lata, maculis luteis conicis aut subquadratis pictd ; apice purpura- 
scente marginali, non exserto ; aperturd albido-cerulescente. 
Long. 0°80 ad 0:90 ; lat. 0°56 ad 0°60; conv. 0°20 ad 0°28 poll. 
Hab. ad insulas Philippinas. 
Operculum almost square, of the form and sculpture of that of 
Nav. tessellata, offering however some characters which the state 
of that. which was submitted to me does not allow me to judge of 
