238 



MUSEUM OF ANIMATED NATURE. 



[PUBPUHA 



"The difficulty of collecting the purple juice, and 

 the tedioui complication ot the dyeing pit>ce8s, made 

 the purple wool of Tyre m> expensive at Rome, that 

 in the time of Augustus a pound of it cost nearly 

 301. of our money.* Notwithstanding this enormous 

 price, such was the wealth accumulated in that 

 capital, that many of its leading citizens decorated 

 themselves in purple attire, till the emperors arro- 

 gated to themselves the privilege of wearing purple, 

 and prohibited its use to every other person. This 

 prohibition operated so much to discourage this 

 curious art, as eventually to occasion its extniction, 

 first in the western and then in the eastern empire, 

 wliere, however, it existed in certain imperial manu* 

 Ctctories till the eleventh century. 



" Gage, Cole, Plumier, Riiaumur, and Duliamel 

 have severally made researches concerning the co- 

 louring juices of shell-fish caught on various shores 

 of the ocean, and have succeeded in forming a 

 purple dye, but they found it much inferior to that 

 lurnishea by other means. The juice of the bucci- 

 num is at first white ; it becomes by exposure to air 

 of a yellowish green, bordering on blue; it after- 

 wards reddens, and finally changes to a deep purple 

 of considerable vivacity. Tliese circumstances co- 

 incide with the minute description of the man- 

 ner of catching the purple-dye shell-fish, which 

 wc possess in the work of an eye-witness, Eudocia 

 Maciembolitissa, daughter of the Emparor Constan- 

 tine VIII., who lived in the eleventh century." 



Mr. W. Cole of Bristol thus describes, in 1084, the 

 process of obtaining the dye of the Purpura la- 

 pi 11 us : — 



" The shells, being harder than most of other 

 kinds, are to be broken with a smart stroke with a 

 hammer, on a plate of iron or firm piece of timber 

 (with their mouths downwards), so as not to crush 

 the body of the fish within ; the broken pieces 

 being picked off, there will appear a white vein, 

 lying tranversely in a little furrow or cleft, next to 

 the head of the fish, which must be digged out with 

 the stiff point of a horsehair pencil, being made 

 short and tapering. The letters, figures, or what 

 else shall be made on the linen (and perhaps silk 

 too), will presently appear of a pleasant light green 

 colour, and, if placed in the sun, will change into 

 the following colours, j". e., if in winter, about noon ; 

 if in the summer, an hour or two after sun-rising, 

 and so much before setting; for in the heat of the 

 day, in summer, the colours will come on so fast, 

 that the succession of each colour will scarcely be 

 distinguished. Next to the first light green it will 

 appear of a deep green, and in a few minutes change 

 into a sea green ; after which, in a few minutes 

 more, it will alter into a watchet blue ; from that, 

 in a little time more, it will be of a purplish red ; 

 afler which, lying an hour or two (supposing the sun 

 still shining), it will be of a very deep purple red, 

 beyond which the sun can do no more. But then 

 the last and most beautiful colour, after washing in 

 scalding water and soap, will (the matter being 

 again put into the sun or wind to dry) be of a fair 

 blight crimson, or near to the prince's colour, which 

 afterwards, notwithstanding there is no use of any 

 stiptic to bind the colour, will continue the same, if 

 well ordered, as I have found in handkerchiefs that 

 have been washed more than forty times ; only it 

 will be somewhat allayed from what it was after the 

 first washing. While the cloth so writ upon lies in 

 the sun, it will yield a very strong and foetid smell, 

 as if garlic and assafcEtida were mixed together." 

 ('Phil. Trans.,' Abr. 11.826.) 



A similar scent was produced by the purple dye 

 of the ancients. 



Mr. Sowerby, in his description of a new species 

 of Sc8laria(Scalaria diadema) from theGallapagos, 

 says, "A fluid secreted by the animal produces a 

 bright purple dye." (See ' Proceeds. 2ool. Soc' 

 1832, p. 5a.) 



We aTe now presented with a patelloid or limpet- 

 like form, constituting the genus Concholepas, 

 which most naturalists regard as closely allied to 

 Purpura. 



These shells, says Cuvier, have the general cha- 

 racters of Puipura, but their aperture is so enor- 

 mous, and their spire so inconsiderable, that they 

 have in a great degree the appearance of those of 

 the genus Capulus, or of one of the valves of an 

 Area. Their notch has a little salient tooth on 

 each side. The mollusk resembles that of the 

 Biiccini, excepting that the foot is enormously 

 broad and thick ; and that the animal is attached to 

 the shell by a muscle in the form of a horseshoe, 

 as in Capulus. The opercu'um is horny, thin, and 

 narrow. 



Lamarck places ConchQlepas in the situation 

 assisjned it by Cuvier. M. Rang observes that he 

 might have well united it to Purpura, as M. de F6- 

 russac had done, adding that M. Lesson's communi- 

 cation respecting the animal which he brought home 

 from the South Sea sufliciently proves that in all 



* riiny nys that ■ pound of the double-dipped Tyrian purple ^ws 

 ■old in liome for a hundred crowns. 



essentials it agrees with Purpura, its operculum alone 

 affording a definite character. The shell is thick, 

 nigose, and ribbed transversely on its external sur- 

 face ; internally the muscular impression of a hoi«e- 

 shoe shape is very visible ; there is no columella. 



2791. — The Pkblvian Coxchoi.epas 



(Concholepat Peruviana). It would appear that this 

 is the only ascertained species (unless indeed others 

 have been recently found) ; but, according to M. 

 Rang, it presents two distinct varieties. It is littoral 

 in its habits, and is very abundant along the shores 

 of Peru and Chile, often attaining to a very large 

 size. 



It is not known in a truly fossil state, but occurs, 

 among other shells on the coast, at a considerable 

 elevation above the sea. The beds of recent shells 

 thus situated prove the upheaving of the line of 

 coast, and that at no great distance of time. 



Mr. Darwin, in his admirable narrative, often 

 alludes to these beds of shells, and the geological 

 facts which their presencfe tends to prove. One in- 

 teresting passage is as follows: — " August IJth, I 

 set out on a riding excursion for the purpose of 

 geologizing the basal part of the Andes, which alone 

 at this time of the year were not shut up by the win- 

 ter's snow. Our first day's ride was northward along 

 the sea-coast : after dark wt reached the Hacienda 

 of Quintero, the estate which formerly belonged to 

 Lord Cochrane. My object in coming here was to 

 see the great beds of shells which are elevated some 

 yards above the level of the sea. They nearly all 

 consist of one species of Erycina, and these shells 

 at the present day live together in great numbers on 

 the sandy flats. So wonderfully numerous are those 

 forming the beds, that for years they have been 

 quarried and burnt for the lime with which the large 

 town of Valparaiso (in Chile) is supplied. As any 

 change of level, even in this neighbourhood, has 

 been disputed, I may add that I saw dead barnacles 

 adhering to points of solid rock, which are now so 

 much elevated, that even during gales of wind they 

 would scarcely be wetted by the spray." 



The configuration, in fact, of Chile, shows that it 

 must formerly have been at a much lower level than 

 at present, and cut up, like Tierra del Fuego, by 

 inlets, bays, and coves, which are now valleys and 

 ravines. 



"Chile," says Mr. Darwin, " as maybe seen in 

 the maps, is a narrow strip of land between the 

 Cordillera and the Pacific, and this strip is itself 

 traversed by several mountain-lines, which in this 

 part run parallel to the great range : between these 

 outer lines and the main Cordillera a succession of 

 level basins, generally opening into each other by 

 narrow passages, extend far to the southward. In 

 these the principal towns are situated, as San Felipe, 

 Santiago, and S. Fernando. These basins or plains, 

 together with the transverse flat valleys, like that of 

 Quillota, which connect them with the coast, I have 

 little doubt, are the bottoms of ancient inlets and 

 deep bays, such as at the present day intersect 

 every part of Tierra del Fuego and the west coast 

 of Patagonia. Chile must formerly have resembled 

 the latter country in the configuration of its land 

 and water. This resemblance was occasionally seen 

 with great force when a level fog covers, as with a 

 mantle, all the lower parts of the country ; the 

 white vapour curling into the ravines beautifully 

 represented little coves and bays, and here and 

 there a solitary hillock peeping up showed that it 

 had formerly stood there as an islet. The contrast 

 of these flat valleys and basins with the irregular 

 mountains gave the scenery a character which to 

 me was very novel and very interesting." 



From this account it is easy to see how beds of 

 unfossilized shells identical with living species, and 

 among them the Concholepas, may occur consi- 

 derably inland, and at a great elevation above the 

 level of the sea. On the island of San Lorenzo 

 (Peru) Mr. Darwin also found satisfactory proofs 

 of elevation within a recent period. In that island 

 extensive beds of shells exist, and he says, "When 

 examiningthebedsof shells which have been raised ! 

 above the level of the sea, on other parts of the 

 coast, 1 have often felt curious to trace their final | 

 disappearance from decay. On the island of San , 

 Lorenzo this could be done in the most satisfactory i 

 manner. At a small height the shells were quite I 

 perfect ; on a terrace eighty-five feet above the sea ' 

 they were partially decomposed, and coated by a \ 

 soft scaly substance ; at double this altitude a thin 

 layer of calcareous powder beneath the soil, without 

 any trace of organic structure, was all that could be ! 

 discovered. This highly curious and satisfactory \ 

 gradation of change, it is evident, could be traced ' 

 only under the peculiar condilions of this climate, 

 where rain never falls so as to wash away the par- 

 ticles of shells in their last stage of decomposition. 

 I was much interested by finding imbedded, together 

 with pieces of sea-weed, in the eighty-five foot bed, 

 a bit of cotton thread, plaited rush, and the head 

 of a stalk of Indian coin : this fact, coupled with , 



another which will be mentioned, proves, I think, 

 the amount of eighty-five feet elevation since man 

 inhabited this part of Peru. On the coast of Pata- 

 gonia and La Plata, where, perhaps, the movements 

 have been slower, there is evidence, as we have 

 seen, that several mammalia have become extinct 

 during a smaller change of level. At Valparaiso, 

 where there exist abundant proofs of elevation to a 

 greater altitude than in this part of Peru, 1 can &\vm 

 that the greatest possible change during the last 

 two hundred and twenty years has not exceeded th« 

 small measure of fifteen feet." 



\ye might enter more fully into this interesting 

 subject ; it is a digression into which, indeed, we 

 have been led very naturally by the statement of 

 the occurrence of the Concholepas with other shells 

 far above I he sea, but which we must not pursue 

 too far. We close it by recommending Mr. Dar- 

 win's 'Journal of the Surveying Voyages of the 

 Adventure and the Beagle ' to those desirous of fur- 

 ther information. 



A group of turriculated shells, constituting the 

 genus Ceritliium, invite attention. 



Cuvier isolates this genus alike from the Bucci- 

 nidse and from the Muricidae, placing it between 

 these two families. The Rev. M. J. Berkelev, and 

 Mr. Hoffman, whose dissection of the mollusk is 

 detailed in the ' Zool. Journal,' vol. v., consider the 

 form as intermediate between the Trochidae and 

 present family. 



The genus Cerithium is numerous both in living 

 and fossil species ; the living species are all marine, 

 with the exception of a few wihich live at the mouths 

 of rivers, and which were separated by Brongniart 

 into a distinct genus, Potaraides, adopted by Cuvier, 

 but which M. Rang observes cannot stand, because 

 it is not based upon characters sufficiently decided. 

 M. de Blainville divides Cerithium into five sec- 

 tions ; but one of these contains the Pirena, which 

 both M. Rang and M. de F^russac place with 

 Melanopsis. 



M. Deshayes enumerates eighty-seven species of 

 living Cerithia, of which two or three only are 

 European. 



In the genus Cerithium the shell is turriculated, 

 and more or less tuberculous ; the aperture is small, 

 oval, and oblique ; the columellar lip very much 

 excavated and callous; the right lip sharp; the 

 operculum is horny, oval, and striated. 



The mollusk is greatly elongated ; the mantle is 

 prolonged on the right side into a canal, but not a 

 perfect tube ; the muzzle is proboscidiform ; the 

 tentacula are distant and ringed, with a medial 

 prominence on which the eyes are seated. The 

 mouth is a simple terminal slit ; the tongue is 

 slender, with reflexed teeth. 



2792.— The Maksh CKBirnuM 



(Cerithium paluslre). The perfect shell belonirs to 

 this species, which tenants the salt-marshes along 

 the coasts in the East Indies. The left-hand accom- 

 panying figure exhibits the animal of Cerithium 

 telescopium. 



2793. — The Madagascar Cesithitim 



{Cerithium Madagascortense, De Blain.). Refer- 

 ring to the two figures, a represents the Cerithium 

 Madagascariense, Lamarck ; and b, the Cerithium 

 Madagascariense according to De Blainville — 

 the Pirena of Lamarck. Though these shells ap- 

 pear to be specifically distinct, it is possible that 

 they may be only varieties. Our impression how- 

 ever is that they are distinct. 



With respect to the habits of the Cerithia, Adan- 

 son, speaking of one of the species, says, that it 

 lives in the sand amongst grass and mangroves, 

 feeding on "scolopendres" and other small marine 

 worms. The individual which formed one of the 

 subjects of the investigation by Mr. Berkeley and 

 Mr. Hoffman, and which was brought from Calcutta, 

 though placed in fresh sea-water, the utmost care 

 being taken to renew it frequently, and though all 

 kinds of marine substances were supplied to the 

 animal for food, refused all nourishment, contenting 

 itself with simply walking over the substances, and, 

 in so doing, touching them with its proboscis. As 

 it would not feed, this individual was killed by im- 

 mersion in spirit. The other specimen, which was 

 anatomized by the zoologists above mentioned, was 

 brought from Ceylon. Mr. Gray (March 25, 1834) 

 read a note to the Zoological Society of I.ondon, 

 giving an" account of the arrival in England of two 

 living specimens of Cerithium armatuni, which had 

 been olilained at the Mauritius, and had been 

 brought from thence in a dry state. That the inha- 

 bitants of land-shells will remain alive without 

 moisture for many months, is, he remarked, well 

 known. He had occasion to observe that various 

 marine mollusca will retain life in a state of torpi- 

 dity for a considerable time; some facts in illus- 

 tration of which he had communicated to the 

 Society ('Zool. Proc.,' part I. p. IIG). The present 

 instance included, however, a torpidity of so long a 



