6 SMITHSONIAN M ISCKIJ.ANEOrS COLLECTIONS VOL. 8l 



is an unusually wide range of variation, but the steps by which it is 

 accomplished are so small and the numbers of individuals are so 

 evenly spaced along the series that the measurements present no 

 features which suggest the inclusion of two species. The same is 

 true of 48 jaws of the Cuban Nesopliontes inicrus. Here the range 

 of variation in length from articular process to front of Wi is from 

 12.2 to 14.6 mm. and that in coronoid depth is from 6.0 to 8.8 mm. 

 One individual (teeth slightly worn) appears to be abnormally small, 

 with the measurements ii.o and 5.8 respectively ; but apart from this 

 exception the variations are remarkably uniform, and again there is 

 nothing to suggest anything else than purely individual variation. 



The series of 42 jaws from Haiti, in striking contrast, is readily 

 separable into two lots on the basis of either one of three different 

 measurements:' (a) distance from articular process to front of Wi, 

 larger form (13 specimens), 13.2- 14.0, smaller form ( 18 specimens), 

 10.0- 1 1.6 ; (b) depth through coronoid process, larger form ( 15 speci- 

 mens), 7.6-8.8, smaller form (17 specimens), 6.0-7.0; (c) combined 

 length of nil and 1112, larger form (12 specimens), 4.50-4.85, smaller 

 form (20 specimens), 3.70-3.85. The teeth in the smaller form are 

 definitely reduced in size as com])ared with those of the larger indi- 

 viduals, a character which is immediately appreciable on comparison 

 of specimens. In the Cuban and Porto Rican series the teeth tend to 

 remain more constant throughout the series. Therefore in those 

 smaller Cuban jaws which approach in size the maximum of the 

 smaller Haitian form the teeth are obviously larger than in the latter. 

 Finally there is no difference in the structure of the heel in the teeth 

 carried by the large and small Porto Rican or Cuban jaws, while in 

 the Haitian specimens an obvious diiference is present.^ Turning now 

 to the skull and the maxillary dentition we find that the contrasts in 

 size between the extremes of specimens from Cuba is about the same 

 as that seen in those from Haiti. The teeth from Cuba, however, 

 are alike in form from the largest to the smallest of 13 specimens, 

 while in those from Haiti there is an obvious difiference in the form 

 of the triangular crown outline in the two largest as compared with 

 five others. A final interpretation of these facts must await the 



' Owing to the fact that some of the mandibles are imperfect it is impossible 

 to obtain all three nieasurements from every individual. 



^ This is so constant that I made only one error in identifying, by this char- 

 acter alone, 26 jaws (18 Iiypouiicriis and 8 paramicrus) submitted to me one 

 at a time by an assistant. The specimens were examined under a magnifying 

 power with which I was unfamiliar, this having the effect of destroying all 

 sense of relative size. 



