8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 82 



not easy to dispose of, namely, the fact that no Plagiodontia or 

 Brotoniys seems to have been carried in the opposite direction to 

 Porto Rico or the Virgin Islands. 



At only two localities have the large and small forms of Isolobodon 

 thus far been found together, in the kitchenmidden at the Kilometer 2 

 site near Monte Cristi and in San Gabriel cave. In the kitchenmidden 

 the remains of the two were mingled together — ten jaws of the large 

 animal among a total of 290. In the cave they occurred separately — 

 the large animal in the culture deposit at the main (south) opening, 

 the small one in the owl deposit near the middle of the long, ascending 

 passage that leads up to the aperture facing north. All the bones in 

 the owl deposit have the appearance of much greater age than those 

 in the midden. The material in which they were found is heavily 

 and uniformly impregnated with lime, while that in the midden, like 

 that in the human deposits in all the neighboring caves, shows no 

 such infiltration except at spots where actual drip from the ceiling 

 is now taking place. The presence of Aphcetreus montanus among 

 the owl refuse may also be an indication of greater age, as this rodent 

 has not yet been found in any midden, though it is the second most 

 common species in the owl-made cave deposits near St. Michel, Haiti. 



On the assumption that Isolobodon portoricensis was introduced 

 by man in the Samana Bay region, these facts would be explained by 

 supposing that the San Gabriel owl deposits were formed before the 

 importation of this larger species and the subsequent extermination 

 of the smaller indigenous form. The process of replacement of the 

 smaller animal by the larger would have afterward become so com- 

 plete throughout the Samana region that no remains of the native 

 species have been found in the deposits left by the Indians. Extending 

 its range westward, Isolobodon portoricensis would have just begun 

 to establish itself near Monte Cristi when both it and the Indians 

 became extinct. 



APH^TREUS MONTANUS Miller 



San Gabriel (owl deposit). — Mandibles, 3. 



These specimens show no peculiarities as compared with jaws from 

 the type locality, near St. Michel, Haiti. 



No bones of Aphcetreus have yet been found in any culture deposit. 



PLAGIODONTIA JEDIUM F. Cuvier 



Plate I, fig. 2 



Anadel. — Imperfect skulls, 2; fragments of palate, 2; mandibles, 

 20 ; odd teeth, 9. 



