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No. lO.—-Genus Amcum.
Species.—A. Searalncus. Lam.
Anm.an.—Unknown to me.
SHEi.L.—Ovate, flattened; aperture with seven teeth ; right lip edged and white; left lip pale coloured and partially reflected; whorls eight or nine ; close. Colour pinkish chesnut, with a few darker marks here and there. Spire short ; body whorl large and forming more than twothirds of the shell; aperture longer than broad and flexuous. Length about seven lines.
I found this specimen on the banks of the Ganges in 1832. But I do not recollect the place, and I made no memorandum of it at the time. It was lying, however, a very little above the water line, on a sand bank. It is the only specimen I have seen.
In “ Burrow’s Elements of Conchology," this shell is described and figured under the Linnaean name of “ Helix Scarabaeus,” in the following manner.
“ Shell ovate, two edged, sub-umbilicate ; aperture toothed.”
" Specimen brown, variegated with pale spots, outer lip and teeth horny, white ; whorls contiguous double convex ; aperture narrow, compressed and fiexuous ; each lip with three teeth; inhabits Asia.”
The plate accompanying this description, and taken from a specimen, at once shews it to be identical with the shell in my possession; but the author errs in saying “ each lip with three teeth,” inasmuch as his plate and my specimen have only one large tooth on the inner lip, three on the right lip, and (in the plate) two large teeth on the body whorl; my specimen has, besides the two on the body whorl, a very minute one arising near the base of one of them, and which, although not noticed by that author, is still nevertheless a distinct and decided tooth.
La Marck says, it is “ seven-toothed.”
Having now given a slight description of each species of land-shells in my collection, I shall, before concluding my letter; mention a circumstance connected with most of them, for which I have not been able satisfactorily to account, nor indeed have I as yet had an opportunity of ascertaining, whether the fact, hereafter mentioned, may be considered as one of the constant habits of the animals, although from the observations I made at the time, I am strongly inclined to think, it may. My attention was first called to the subject, while searching for Pupm No. 6.
When proceeding in December, 1832, to join my regiment, my route lay, from Futtehpoor Sikra to Neemuch, chiefly through a range of low rocky hills, and observing great numbers of these Pupae, dead, in ravines and on banks of nullahs, I naturally concluded that living
88 On the Land Shells of India. [F EB.
specimens might be found in the hills, and accordingly whenever our encampment lay within a moderate walking distance, I set forth, after breakfast, with sundry apparatus for digging up and securing whatever prize I might be lucky enough to meet with.
For the first day or two my search for shells was inefiectual, and I returned to my tents tired, and puzzled to account for my had success, until at last, we encamped between two detached hills. Here I once more commenced a search, which for several hours proved as unsuccessful as before; but the day being cool, and the surrounding scenery very beautiful, I climbed up the rocks and crossed over to the eastern side, where I again commenced a search, which in a very short time was rewarded with a more abundant supply of living Pupae than I had ever thought of obtaining.
These were buried deep in the earth, where they might undoubtedly have remained, safe from prying eyes, had not a little mouse, fortunately enough for me, selected that very spot, whereon to sink its subterranean retreat, and thus unconsciously betrayed the hidden treasures.
The circumstance of these shells being found only on one side of this rock, induced me to go and examine the one on the opposite side of our encampment, and there also I found Pupas deeply buried in great numbers, but only on the eastern aspect.
From this time I made a point of inspecting the neighbouring hills, whenever within easy distance, sometimes finding no shells, while_ at others I found them in abundance, and invariably facing towards the E. or S. E. In company with these, I found at different places a few specimens of Bulimus (No. 5), Papa (Nos. 7 and 8), and Succinea (No. 9).
I now began to recal to mind the situation in which I had found Bulimus No. 5, and Pupa No. 8, at Mirzapoor, and they also were decidedly only to be found on the S. E. side of my Bungalow; and moreover, lam nearly certain that Helix, No. 3, found at Tara, was also on the eastern aspect. Pupa No. 7, and Succinea No. 9, as also numbers of Pupa No. 6, were found on the rocks at Beana, facing to the same direction; and Bulimus No. 4, although a few were found elsewhere, were by far more numerous on the eastern side of the trees, than on the others ; and this also I observed at the commencement of the rainy season at Neemuch.
Having therefore satisfied myself that all the living species of land shells, which I have collected, were found on or nearly an the same aspect, viz. eastern or S. E. ; it only remains to ascertain the cause of such partiality, and as this is most probably connected with the welfare of the animal, it may be concluded that the all-wise Director of nature has imparted aninstinct to these tender beings, which enables them to choose the
situation most favourable to their wants and safety. May not, therefore, the fact of their being found-on the eastern aspect of the rocks and trees be accounted for, by supposing it to originate in a desire to find shelter from the western blast during the dry heats of summer, and to be in a situation to enjoy the first refreshing and invigorating showers of the rainy season?
I have put the above as a query, because I am not certain that the rains prevail from the eastward or south-eastward, although at this station they have certainly done so this year. I shall however take every opportunity of ascertaining, whether the above is a constant habit of the land shells or not, and in this I hope I shall be assisted by others of your correspondents who may be willing to pay attention to the subject.
PART 2.—On the Fresh-water Univalves.
No. l.—Genus AMPULLARIA.
AMPULLARIA.—-Found. in jheels; Mr. Bnnsorfs description of the animal, as far as I have been able to ascertain, is perfectly correct. Operculum calcareous?
Var. With longitudinal brown bands; found with the last, in jheels at Mirzapoor.
I have one large specimen with stripes, which is indeed the only one I have seen, but the young ones are Very commonly met with. Operculum calcareous.
No. 2.—-PALUDINA, Bengalensis .9
This is a very common shell, occurring plentifully in most jheels and stagnant nullahs. In the J egu nullah at Chunar they are in abundance, but the first specimens I procured at Humeergurh near Neemuch, in a large jheel. The animal is beautifully studded over with black and orange coloured spots.‘ It is ova-viviparous; from one I obtained 102 young ones. Length of the shell from 1% to 2 inches. The young have a ridge or keel on the body whorl, which makes the aperture subtriangular; this is lost in the mature shell.
The umbilicus of the shell varies much in difi'erent spicimens, some shewing scarcely any, while others have it very well defined and rather deep.
The shell is covered with an olive-green epidermis and longitudinally striped with brown; on the body whorl these stripes are nine in number, and are placed alternately, a narrow one and a broad one. Operculum corneous.
In jheels and stagnant nullahs. '
This has a broad brown band running longitudinally from the apex to the aperture. "
The young are keeled like those of the last species. Length about one inch-—~aperture with a bleak horny rim. Operc. corneous.
Found in a large jheel near Chunar.
The spire very much corroded. Colour pale olive-green. Aperture with ablack horny rim. One of those produced 27, and another 87 young ones; they have the ridge and the sub-triangular aperture when young. Length from nine lines to an inch. Animal orange and black. Operc. corneous.
Found in the J egu nullah at Chunar.
Shell solid and thick, pale green, interior white. Little more than an inch in length. Operc. corneous.
Found in a very large jhil near Chunar. Colour dark olive-green, and longitudinally striped with 10 black stripes, alternately narrow and broad. Spire corroded; margins of the mouth with a horny rim. This shell is more globular than any I have seen, belonging to the Genus Paludina. I have only two of them, and the animal is unknown to me. Operc. corneous.
I No. 7.—VALVATA ?
This is the shell of which a description appeared in the 9th No. of the Journal, under the head of Notes on the Habits of the Paludina.
These shells diifer much in the development of the umbilicus, some having it well defined, others having scarcely any. Operc. calcareous.
This I found at Mirzapoor, at the foot of trees, in puddles of water.
These I have seen in abundance on the banks of the Ganges and nullahs, but always dead and injured from exposure to the sun. The only living onesl have seen, I found at Dhuni in the Jypoor territory, under a wall enclosing one side of a dirty tank. The spire of these is not corroded like the last species, nor has it any umbilicus; aperture angular above and below. Operc. calcareous.
No. 9.—VALVATA P Found with No. 7, at Mirzapoor.
The aperture only angular above.
No. l0.—PLANORBI5, Corneus .9 These may be found in almost every jheel or stagnant piece of water. Like all the fresh-water univalves, they bury themselves in the mud, as the water evaporates during the hot seasons of the year. I brought a _lump of dry clay from the bed of a jheel at Mirzapoor, to Neemuch, and
having kept it for a year, I found on immersing it in water, that the shells imbedded in it, were still alive and healthy. Diameter %’;- inch. ' No. 1l.—-VAR.? Pmnonnrs.
These I brought from Mirzapoor, and have marked them as a variety, on account of their form being more regular, than the last; they were found plentifully, and may probably prove the young of Planorbis No. 10.
The whorls in this species are very much flattened.—The aperture opening obliquely and oval—shell thin and diaphanous—whorls 4 or 5 in number—diameter 3% lines.
The exuvia common on the Ganges.—They are found in stagnant waters—more frequently in nullahs than in jheels.
No. l3.——PLANOB.BIS. Animal blackish. The shell minute,'of three or four whorls, which are rounded; aperture oblique; diameter about 1% line.
These very small shells I- found during the hot winds of 1833, in the earthen pans containing the water for my tatties. They were drawn from a well in my compound, '_the bottom of which is hard traprock, and also from one other well near my house. How they got into these wells I cannot conceive, as there is no nullah or pond near them. They were not abundant.
These I found on the banks of the Ganges among exuviae. They are
injured by exposure to the sun. They inhabit rivers. No. 14.
A smaller size. These appear to be the same as the foregoing. I obtained them during the hot winds, from the same well in which the small Planorbis, No. 13, was taken. This is a curious fact, as the bottom of the well is hard trap-rock, and unless the animals burrow into the sides of the well, they cannot possibly find protection at the bottom of it. In this well there is no true spring, it being supplied merely by the water soaking down from the surface during the rains.
I have one specimen, which was given ne by a friend of Mr. BENsoN’s, from whom he obtained it. The epidermis is dark olive green. Shell 2 inches long. The body whorl longitudinally tuberculated.
This species, of which I have only one specimen, is of a blackish colour.
Transversely wrinkled on the whorls. Length 1% inch.
This I found in a nullah at Chunar, which with the exception of the
rainy season, at which time it joins the Ganges, is strictly “stagnant
water.” The animal was alive, and in soft mud.