B O L C A. 



. 



643 



Bo!m. the island of Japan. One individual, of small size, 

 * ' has come unde the inspection of a celebrated na- 

 turalist ; but another, considerably larger, though 

 in a fossil state, has been taken from the excavations 

 of Bolca. The fcttr is ten inches in length, from 

 j < - ' ^ j "" ""feme 

 head to tail, and nineteen and a nan m ... 



breadth : Several of the pectoral and ventral fins are 

 defective, but their origin is still quite conspicuous. 

 Two other specimens of the same fish are likewise ex- 

 tant. A species of ray, which is scarce to be re- 

 cognised in the European seas, was found in the im- 

 mediate vicinity of Bolca, along with three univalve 

 fossil shells imbedded in the same stone. It is twen- 

 ty-three inches long, and nine broad, and exactly 

 resembles a new species inhabiting Arabia, called 

 raja sepken ; some are discovered three or four times 

 as large. The fishes of Mount Bolca are by no 

 means confined to genera and species now extant ; for 

 various specimens have appeared hitherto imdescri- 

 bed, and which are still unknown. The uranoscopus 

 rastrum, so named in its fossil state, has never been 

 seen as a living animal ; and the most careful compa- 

 risons of all the specimens found, remove it from any 

 analogous species. We shall dwell no longer ononis 

 division of the natural products of Bolca ; catalogues 

 ef which have been published in Italy, shewing what 

 species belong to the seas of the four quarters of the 

 globe, and what are exotic fresh water fishes. Be- 

 sides these, several rare species of fossil crabs are ob- 

 tained from the quarries, such as the longimaniis, se- 

 tifer, and locusta, of which the specimens are parti- 

 cularly fine. Among the insect tribes, there have 

 been dug up an oniscus, oestrus, two asili, and an 

 American cimex. Complete exuviae of marine ser- 

 pents are sometimes, though rarely, laid open ; and 

 numbers of marine plants are imprinted on the stones. 

 The parts of birds are less frequent in a fossil state 

 than those of any animals; but a petrified quill was 

 once found in Bolca, and lately preserved at Verona, 

 as an exception from the general rules of nature in 

 accomplishing this extraordinary transition. 



A profound and interesting problem arises on the 

 formation of this singular hill, and the substances 

 which it contains. First, How can such an aggre- 

 gate of animals, inhabiting regions so many geogra- 

 phical degrees asunder, have been collected in so li- 

 mited a space ? Secondly, How are the fishes inha- 

 biting salt and fresh waters respectively, which may 

 almost be denominated different elements, intermixed ? 

 And, thirdly, How have the bodies of such soft and 

 destructible animals been able to resist the usual de- 

 composition of nature, undergo a transition to stone, 

 and remain entire from a period of such remote anti- 

 quity ? Various theories may be offered on these 

 questions, which, in this place, we shall not pre- 

 tend to discuss, as they will partly come under our 

 consideration in other articles. But there are some 

 points which peculiarly relate to Mount Bolca it- 

 self, on which we shall make a few observations. 



It is evident that the sea has once overflowed the 

 highest mountains. Beds of shells, <uid strata of cal- 

 careous substances, added to the impression of fishes 

 on stone, besides many other concurring circumstances, 

 prove the truth of this assertion. It is clear, there- 



fore, that the Veronese territory, which presents all 

 these indications in the most conspicuous manner, ' 

 may have anciently been submerged, or even may have 

 been the bottom of the sea. In various portions of 

 the globe the waters have receded ; and we know, 

 that, in certain places, their gradual retreat has been 

 " ' '-* -"- ""<-fasive ages. At the same 



slowly exniDiceu u u ' -- at 



time, it is not improbable that they may here iia^ . 

 once been withdrawn by some violent convulsion or 

 the earth ; a fact which has been exemplified in the 

 course of the preceding centuries. But supposing 

 that they naturally covered the Veronese territory, it 

 is far from easy to account for the diversity of fishes 

 belonging to remote climates being found in the same 

 spot, especially as the heat of the torrid zone seems 

 indispensible to their existence. Yet, without recur- 

 ring to the gradual refrigeration of the earth, or the 

 gradual change of-climate in limited districts, which 

 we are well assured has followed, two circumstances 

 ought to be preserved in view : Nothing can be more 

 imperfect than our acquaintance with the finny tribes. 

 Genera and species innumerable have never met the 

 eye of mankind ; and it is justly remarked by a mo- 

 dern ichthyologist, that our principal knowledge of 

 their distinguishing characters have first been derived 

 from those served up at our repasts. Can we affirm 

 with confidence, that any fish of the Mediterranean is 

 unknown in the Pacific Ocean, or that many in the 

 Greenland Seas do not frequent the shores of Bri- 

 tain r Skilful naturalists are aware, that animals are 

 daily discovered in one region, that have been refer* 

 red to and described as peculiar to another ; and that, 

 with care and attention, even when removed from 

 their original liberty, they may be preserved and 

 propagated in climates not naturally their own. Nei- 

 ther can we overlook an important fact, relative to 

 the temperature of the elements, which terrestrial 

 and aquatic animals respectively inhabit. The air 

 is subject to constant vicissitudes from external causes, 

 but it is probable that the temperature of a vast body 

 of water always continues at nearly the same degree ; 

 nay, it is probable, that, with the exception of ex- 

 treme cases, the temperature of the sea, above fifty 

 fathoms deep, is not very different all over the world. 

 Hence it is possible, supposing the genera of Mount 

 Bolca and those of the Indian Seas to be identified 

 beyond dispute, that both may have enjoyed a requisite 

 degree of temperature when a deep sea covered the 

 territory of Verona. Fishes, however, are more pri- 

 vileged than terrestrial animals, in the facilities of 

 seeking a temperature agreeable to themselves ; if the 

 surface of their element undergoes refrigeration, they 

 have only to plunge farther into its depths ; and the 

 body being too immense to be susceptible' of suddeH 

 vicissitudes, they have time to withdraw from one 

 parallel of latitude to another, as their sensations may 

 require. We know, that certain fishes can support a 

 considerable change of climate without injury ; and 

 that some, transported north from places far to the 

 southward, have been naturalized. Thus, we can- 

 not with absolute confidence maintain, that the fishes 

 hitherto thought peculiar to the warmer climates 

 could not live in the seas covering Mount Bolca, or 

 that they did not enjoy that degree of temperature 



Bolca. 



