OF SOUTHERN INDIA. 11 
quently nearly parallel to the horizontal plan of the basis, facing the same; the 
outer peristome is largely expanded and reflexed, its margins being connected by 
the inner lip of about the same thickness. No dentition is perceptible in the 
interior of the aperture, although it may exist farther inside, whence the rock 
could not be taken out. The specimen, being unique and so far complete as to be 
easily recognised and characterized in its principal features, is too valuable, to 
sacrifice it to the examination of the inner space of the aperture. The lateral 
portion of the outer peristome is in the specimen a little corroded. 
As regards general form and number of Bauer ey our specimen recalls much 
the European Anch. holoserica Studer. 
Locality. Near Ninnyoor: the single specimen occurs in pinkish limestone. 
Formation. Arrialoor group. 
3. ANcHIstoMA ARCOTENSE, Stoliczha. Pl. I, Fig. 7. 
A. testa discoidea, planorbulari, supra pland, subtus late umbilicata; anfracti- 
bus quinis, angustissimis, lente crescentibus, supra convexis, sutura profunda junctis, 
omninris in wnbilici spatio conspicuis, centralibus (14) levibus, politis, ceteris transversin 
oblique costulato-striatis, striis lateraliter atque infra tenuioribus sew obsoletis ; 
ultimo anfractu supra quoddan prominente, prope medium altitudinis latissimo, ad 
umbilict marginem rotundate angulato, antice parum deflexo; apertura obliqua, 
semielliptica, lateraliter angustiore ; peristomate exteriore parum dilatato, expanso 
et vix reflexo, prope medium wnidentato ; labio calloso. 
Height of shell: transversal diameter (taken as 1:00) ... Hee a. 0°35 
Width of one whorl above: transversal diameter at Ace vaiags Onl: 
A planorboid shell, consisting of five volutions, being laterally much narrowed, 
higher than broad, convex above and separated by a deeply impressed suture. 
All the whorls are visible in the space of the umbilicus, which is very large and 
the margins of which are, on the last whorl, slightly angulated. The greatest 
width of the whorls is near to, but still a little above, the middle; the central or 
embryonal whorls, comprising about one and a half volution, are slightly elevated 
above the somewhat immersed plane, shining and smooth; the others are covered 
above with pretty strong oblique striz, which disappear below. The last whorl is 
not much deflected; aperture oblique, semi-elliptical and according to the size of the 
whorls higher than broad. The outer lip is expanded, strongly reflexed and inside, 
somewhat below the middle, provided with a short pointed tooth; the inner lip is 
callose, only partly visible on our specimen, the adherent rock preventing a view 
into the interior space. This makes it uncertain whether any other dentition is 
present or not. We must await other materials for this purpose; although, save a 
small portion of shell-surface near the mouth, our specimen is quite perfect. 
This species, which is very like the South-European H. (An.) anigyra, Ziegler, 
is readily distinguished from the former by its narrower whorls and the less 
deflected anterior portion of the last. 
