ROOM VI. OSSIPEROUS CAVES OP THE BRAZILS. 481 



of which we have already spoken ; as, for example, the Scelidothe- 

 rium, Glyptodon, Clamydotherium, &c. ; of these there are many per- 

 fect bones, and portions of the dermal cuirass of the two latter. In 

 this collection there are several bones of a very large species of that 

 extraordinary carnivore described in a former section, (ante, p. 400,) the 

 Machairodus, and of existing genera of mammalia, including Monkeys, 

 Opossums, &c. ; there are also shells of the large bulimus, a common 

 terrestrial mollusk of South America. 



There are likewise remains of a species of Hyena and Horse ; the 

 former genus, which abounded in Europe during the newer tertiary and 

 drift period, is now only known to exist in Asia and Africa ; and the 

 latter was extinct in South America when the Spaniards invaded that 

 country, though numerous relics occur of a species of Equus, that was 

 contemporary with the colossal Edentata, whose skeletons are imbedded 

 in the Pampas. Thus the ancient Brazilian fauna differs as essen- 

 tially from the modern one, as that of the Cave period of Europe 

 from the existing assemblage of terrestrial mammalia. 



An interesting fact relating to the Brazilian caves is worthy of record. 

 M. Claussen, in the course of his researches, discovered a cavern, the 

 stalagmitic floor of which was entire. On penetrating the sparry 

 crust he found the usual ossiferous bed, but pressing engagements 

 compelled him to leave the deposit unexplored. After an interval 

 of some years M. Claussen again visited the cavern, and found the 

 excavation he had made completely filled up with stalagmite, the floor 

 being as entire as on his first entrance. On breaking through this 

 newly formed incrustation, it was found to be distinctly marked with 

 lines of dark-coloured sediment, alternating with the crystalline stalac- 

 tite. Reasoning on the probable cause of this appearance, M. Claussen 

 sagaciously concluded that it arose from the alternation of the wet and 

 dry seasons. During the drought of summer, the sand and dust of the 

 parched land were wafted into the caves and fissures, and this earthy 

 layer was covered during the rainy season by stalagmite, from the water 

 that percolated through the limestone, and deposited calc-spar on the 

 floor. The number of alternate layers of spar and sediment tallied 

 with the years that had elapsed since his first visit; and on breaking 

 up the ancient bed of stalagmite, he found the same natural register of 

 the annual variation of the seasons; every layer dug through presented 

 a uniform alternation of sediment and spar : and as the botanist 

 ascertains the age of an ancient dicotyledonous tree from the annual 

 circles of growth, in like manner the geologist attempted to calculate 

 the period that had elapsed since the commencement of these ossiferous 

 deposits of the cave ; and although the inference, from want of time and 

 means to conduct the inquiry with precision, can only be accepted as 

 a rough calculation, yet it is interesting to learn, that the time indicated 

 by this natural chronometer, since the extinct mammalian forms were 

 interred, amounted to many thousand years. 1 



As in the bone-caves of England, France, and Germany, relics of 

 human skeletons have been found in the upper layers of the detritus 



1 Communicated to me by Mr. Waterhouse. 

 I I 



