282 ME. BUSK ON THE EBMAINS OF 



The anterior angle of the shaft is more acute in fig. 21, and it is continued down 

 towards the inner malleolus in a more pronounced manner. On the posterior aspect 

 fig. 21 is much more concave at the upper part; and the outer posterior angle is con- 

 tinued, tolerably distinctly, quite to the lower end, whilst in fig. 16 it is not continued 

 below the middle of the shaft. The posterior surface of the bone, consequently, in 

 fig. 16 is more evenly rounded on the outer side than it is in the other, as shown in fig. 16 h. 

 The difference in the contours of both the upper and lower epiphysial surfaces is shown 

 in the subjoined outlines, and is, as it appears to me, much greater than can be attributed 



Ci9 v7 



to mere individual variety or to difference of age. It may in addition be remarked that 

 the nutrient foramen is placed much higher up in figs. 20 and 21 than in the other. 

 In all the respects above referred to, except in size, the bone represented in fig. 17 agrees 

 with fig. 16, and fig. 20 in like manner with fig. 21. 



If, upon such imperfect data, one might speculate as to the species to which these two 

 forms of tibia should be assigned, it would seem most likely that the type shoAvn in 

 fio-s. 16 and 17, from its greater robustness, belongs to E. melitensis, and the other to 

 E. falconeri ; but upon this I refrain from expressing any positive opinion. But, besides 

 the five specimens thus disposed of, the collection contains three other equally young, 

 if not younger, tibiae, of a totally different type. 



Two of these tibiae are shown in PI. LI. figs. 38, 38 a, and 39, 39 a ; and their 

 peculiar character as distinguished from the others will be at once obvious. The one 

 represented in fig. 39 appears to have had a sort of spongy exostosis springing from the 

 inner side of the head, which gives it a very bizarre appearance in the back view 

 fig. 39 «* ; the smaller specimen, therefore, shown in fig. 38, affords better materials for 



* The artist has inadvertently drawn the inner face of the bone in fig. 39 instead of the proper anterior 



