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sculptilis, B. which, however, is easily distinguished by the characters of its crenulated peristome, besides other peculiarities.
The Alycasus from the Andaman islands lately described by Mr. Benson (Ann. and Mag. Nat. Hist. for January, 1861) probably resembles A. Ingrami in size and general shape. I have not had the opportunity of seeing A. Andamaniaa, B. which is, however, clearly distinct from the present species on account of the characters of the spire, suture, sculpture, &c.
I have much pleasure in naming this form after Captain Ingram, to whom I am indebted for a very large collection of shells, chiefly from Arakan and the Arakan hills, and embracing altogether about 50 species, several of which had escaped my own search._
A. Ingra/ni was found in only one spot, viz. in earth at the sides of a large mass of limestone about 3 miles S. W. of Tongoop. There it was abundant.
2. ALYOJZUS IIUMILIS, n. s.
Testa aperte umbilicata, turbinato-depressa, l:evis, rubello-succinea, ad apicem sanguinea. Spira conoidea, apice obtusula, sutura profunda. Anfr. 3% rotundati, ultimus ad latus mediocriter inflatus et confertim costulatus, tum coustrictus, versus aperturam breviter descendens. Strictura glabra, longa, antice tumidior. Tubulum suturale breve, % peripheries subzequans. Aperture, obliqua,circu1aris; peristoma duplex ; externo retro-relicto, interno continuo, porrecto, fore solutc. Operculum corneum, multispirum, externe concavum.
Diam. maj. 2% or 0.1
Hab. ad Akouktoung, ad ripas fluminis Irawaddi, in provincia Burmana Pegu.
A solitary specimen of this species, slightly weathered and shewing more sculpture than usual, was found by me in April, 1861, close to Myanoung, on the banks of the Irrawaddy. With it I found a few other shells; amongst them a small variety of Bulimus camopictus, Hutt. and as this shell is not known to inhabit Pegu, but has since occurred to me in the neighbourhood of Ava, I was inclined to suppose that A. humilis was also derived from that neighbourhood. Lately, however, during a. hurried. search at Akouktoung, I had the good fortune to find some living specimens of what, I have little doubt, is the same species as that which I first obtained, the only diiference being the absence of any sculpture except on the tumid portion of the last whorl. From those specimens the above description has been corrected.
A. kumilis resembles somewhat the minute A. armillatus, B. but dilfers in the very much greater distance to which the strongly marked costulatiou upon the tumid portion of the last whorl is carried back from the constriction, the distance being in both species proportional to the length of the sutural tube. A. humilis is further distinguished by its longer constriction, by the descent of the mouth, and the greater tumidity of the last whorl. The colour, as in many Alycwi, is probably not quite constant, some specimens being white and translucent.
With A. fiumilis at Myanoung I found a. single broken specimen of another Alycwus which resembles the singular little Darjiling A. plectocheilus in the form of the peristome. The specimen being imperfect and weathered, I delay publishing a description of it in the hopes of succeeding in obtaining better specimens before doing so.*
Testa pcrforata, ovato-globosa, tenuis, pallide fulva, costulis fila.ribus subremotis sinuatis ornata. Spira ovato-conoidca, lateribus convexis, apicc obtusula, sutura impressa. Anfr. 41, rotundati, 2 primi lente, penultimus et ultimus celerius accrescentes, ultimus ad latus vix tumidus, pone stricturam spatio brevissimo confertius costulatus, tubulum suturale brevissimum gerens. Spatium constrictum lznve, costulfi filiformi unit medio plerumque signatum, prope aperturam tumidius. Aperture. vix obliqua, majuscula, circularis; peristoma. duplex; interno breviter porrecto, continue; externo expanso, retro relicto, ad umbilicum reflexo, perforationem partim celante.
Apcrt. diam. 1% 0.06
' It is perhaps the same as a species since found in Upper Burma.
Habitat in montibus Arakanensibus provinciam Burmanam Pegu ab Arakan secernentibus.
A Burmese representative of the little Darjiling group of Alyceei, which comprises A. constrictus, B. A. Bembex, B. and A. Otipfi0rus, B. A. graphicus, although much more globose than any of the others, is in some respects intermediate between constrictus and Otipkoi-us, resembling the first in size and somewhat in form, and the latter in the reflexed left edge of the outer peristome. This character, however, is by no means so much developed in the Burmese as in the Darjiling species. The present has a more marked sculpture than either of its three allies and differs from them also in the very slight approximatiorof the costulation behind the constriction. Almost all the species of the genus Al_1/cwus, are more closely and strongly marked upon the tumid portion of the last whorl than on any other part of the shell, the length of the closer ribbing and of the tumidity having a. general relation to that of the sutural tube.*
Several dead specimens-of A. graphicus were found at Moditoung, a halting-place about 55 miles from Prome, on the road across the uninhabited Arakan Yoma. range from that place to Tongoop.
4. Amzcmus v1<".s'r1'rus, n. s.
Testa. subanguste umbilicata, turbinata, solida, epidermide deciduii, crasséi, subtestaceii, sordide albidfi, conferte, ad spatium inflatum confertissime costulatii, induta, sub epidermide rubella, laevis, spatio inflato costulato-striata. Spira conoidea, apice obtusa, sutura. impressa. Anfr. 4%; rotundati, ultimus teres, ad latus parum inflatus. Strictura brevis, versus aperturam vix tumidior. Tubulum suturale mediocre. Apertura fore verticalis, circularis, majuscula: peristoma duplex ; interno continuo, externo cxpansulo, ab interno sulco separate, ad anfr. penultimum breviter interrupto.
Diam. maj. 5 or 0.2
Hab. in montibus Arakmiensibus.
" .4. otiphorus, B. is not costnlatcd, but simply, closely and regularly striated throughout, rather more closely and costulately on the inflation.
Hab. cum A. gmphico ad Moditoung.
But a single specimen of each variety was found. The first was obtained on the banks of the Pado Khyoung, a stream running from the Arakan range on the Pegu side in the district of Henzada. Asingle specimen either of another variety, or of a distinct but closely allied species occurred to me on the banks of another stream, the Alon Khyoung, lying between the two previously mentioned localities. This form differs in having a simple lip, and, apparently, a‘ longer sutural tube. None of the specimens are quite fresh, although all are in fair condition and unbleached. Of the epidermis only traces remain on both shells.
This species is not aflined to any known form. It is perhaps nearer to the little group to which A. graphicus belongs than to any other, but it has not the short sutural tube nor the ovately conoid form which characterizes that section of the genus. The shortness of the constriction, and the very slight degree in which it expands
towards the aperture, connect this form somewhat with the section Dior;/a: of Mr. Benson.
5. Anyozsus snoonrnus, n. s.
Testa aperte umbilicata, dcpresso-turbinata, acute sinuato-costulata, succinea, translucens, Spira conoidea, apice obtusula, sutura. imprcssa. Anfr. 4.<, ultimus ad latus inflatus, ibidem confertissime costulatus. Strictura longa, medio tumida, et duobus vel tribus costulis obliquis, sulculis internis correspondentibus, signata. Tubulum suturale mediocre, % pcriphcrize submquans. Apertura obliqua, irrcgulariter circularis, supcrne subangulata: peristoma duplex; intcrno continuo, incrassato, expansulo, margine dextro bis obtuse angulato, ad basin canaliculo hand intrante perforate; externo breviter cxpanso, ret1'0 relicto.
Diam. maj. 5 or 0.2
Habitat in montibus Arakancnsibus.
Some of the peculiarities of this species, such as the canaliculate base of the peristome, and the two or three small plaits on the constrictions are repeated in that next described. The plaits or ridges just referred to, although they have corresponding internal hollows, are scarcely so prominent as those forming the sculpture of the upper portion of the shell. They are nearer to the mouth than to the rise of the sutural tube, and rest upon a tumidity which is scarcely sulficiently pronounced to enable the species to be assigned to the section Clzarax of Benson, although it exactly represents the 'well marked ridge in the undermentioned species A. polygonoma. The sutural tube is, in one specimen, somewhat short of the typical length.
Of A. succineus, I only obtained 41 specimens. They occurred at Moditoung together with A. graphicus, &c. All were dead, but in fresh condition.
6. Anronsus POLYGONOMA, n. s.
Testa aperte et perspective umbilicata, turbinata, radiato-striata, rubello-succinea. Spira conica, apice obtusula, sutura profunda. Anfr. lt rotundati, ultirnus ad latus valde inflatus, ibidem confertissime et acute costulatus; spatium constrictum longitudinis mediocris, costulato-striatum, medio in costam prominentem, intus cavo-sulcatam, 2 vel 3 costulis signatam,tumescens. Tubulum suturale mediocre, % peripheriae subsequans. Apertura obliqua, polygonalicireularis, basi valde antice sinuata ; peristoma duplex; interno vix porrecto, margine dextro tor subangulato, basi subcanaliculato; externo incrassato-expansulo, processu brevi, acuto, basali munito.
Diam. maj. 5 or 0.2
Hab. in montibus Aralianensibus.
This species is allied to the last described but is distinguished by its higher spire, less marked sculpture, by the strong ridge on the constriction, and by the more polygonal aperture. The incision of the base, however, is slighter, and, in this species, accompanied by a slight corresponding projection beneath, which represents, on a small scale, the large ear-like basal process in A. prosectus Bens. from the Khasi Hills. The inner pcristome of that species also has a slight basal indentation within the aperture.
I am indebted for afew perfect specimens of this species to Captain Ingram, who found them upon the \Vestern side of the Arakan range.