ORIGIN OF CAVE LIFE. 25 



were inhabited by postpliocene mammalia and shells. The caves 

 of Anguilla include remains of twelve vertebrates,* of which seven 

 are mammalia of extinct species, and several of them are of large 

 size. These are associated with two recent species of molluscs 

 Turbo pica, and a Tudora near pup&formis.'f As these large ani- 

 mals no doubt required a more extended territory for their support 

 than that represented by the small island Anguilla, there is eA^ery 

 probability that the separation of these islands took place at a 

 late period of time and probably subsequent to the spread of the 

 postpliocene fauna over North America." 



I think the reader will conclude from the facts Prof. Cope so 

 clearly presents, that the subterranean fauna of this country does 

 not date back of the Quaternary period. These species must have 

 been created and taken up their abode in these caves (Mammoth 

 Cave and those of Montgomery Count} r , Virginia) after the breccia 

 flooring their bottoms and containing the bones of Quaternary ani- 

 mals had been deposited ; or else migrated from Tertiary caves 

 farther south, which is not probable, as it has been previously 

 shown that those blind animals inhabiting wells immediately die 

 on being exposed to the light (British Sessile-eyed Crustacea, i, 

 p. 313), though the blind craw fish is not thus affected. 



The case becomes much simpler when we consider the age of 

 the rocks in which the Adelsberg and other caves mentioned by 

 Schiodte are situated. The Alps were under water in the Middle 

 Eocene ; consequently the caves could not have been formed until 

 the close of the Tertiary. Hence the species of the cave fauna 

 were evidently created either at the close of the Tertiary, or more 

 probably the beginning of the Quaternary, as "even in the later 

 part of the Pliocene era there was an elevation of three thousand 

 feet in a part of the Island of Sicily" (Dana). We are therefore 

 led to conclude that the species of the subterranean fauna the 

 world over are recent creations, probably not older than the ex- 

 tinct mammals associated with man. 



*Loc. cit. 1839, 183; 1870, 608. A fourth species of gigantic Chinchillid has been found 

 by Dr. Rijgersma, which may be called Loxomylus quadrans Cope. It is represented by 

 portions of jaws and teeth of three individuals. It is one of the largest species, equal- 

 ling the L. latidens, and has several marked characters. Thus the roots of the molars 

 are very short, and the triturating surface oblique to the shaft. The roots of the second 

 and fourth are longer than those of the first and third. The last molar has four dental 

 columns instead of three as in the other Loxomyli, and is triangular or quadrant-shaped 

 in section ; the third is quadrangular in section, and has three columns. The second is 

 the smallest, being only .(> the length of the subtriangular, first. Length of dental series 

 m .063 or 2.5 inches. Palate narrow and deeply concave. There is but little or no lat- 

 eral constriction in the outlines of the teeth; the shanks are entirely straight. In its 

 additional dentinal column, this species approaches the genus Amblyrhiza. 



The large Chinchillas of Anguilla are as follows, Loxomylus lortgide 

 quadrant* , and AmUi/rhiza inundata. 



fSee Bland, Proceed. Amer. Phil. Soc., 1871, 58. 



