186 



A. LEITH ADAMS ON MALTESE LAND- TORTOISES. 



and inner aspects, and also a portion of the distal end in front. As 

 regards size, it is about a third longer than fig. 4, and, as will be seen 

 presently, differs from it morphologically. Both bones represent aged 

 individuals, as is well shown by their gnarled appearances. More- 

 over, relatively, they are stouter than the tibise of T. elephantopus 

 and T. ephippium, and come closer in that respect to T. vidua. 

 I conceive that the larger (fig. 3) belonged to T. robusta, and the 

 smaller (fig. 4) to T. Spratti. 



The following establishes their proportional greater thickness as 

 compared with certain recent species that I have been enabled 

 to examine : — 



Length of tibia 



Least girth of tibia 





«o 











S 









§ 



* 











-Cj 









I< 



g 

 e 



*3 





•K> 





Kg 



-IT 



.8 



CO 



«3 



^ 



Eh' 



^ 



^ 



Eh 



millim. 



millim. 



millim. 



millim. 



millim. 



150 



136 



129 



115 



85 



72 



60 



57 



73 



53 



Thus it appears that the smallest girth of the shaft in T. robusta is 

 greater than that of the tibia of the more slender T. ephippium, 

 which is 2-2 inches longer, and that, whilst the antero-posterior 

 diameter of the femoral articulation is 41 millimetres in T. robusta, 

 it is 38 millimetres in T. ephippium ; but their distal articulations 

 are about equal in size. 



The tibia of Testudo Spratti has the groove on the astragalo- 

 calcaneal aspect deep (Plate VI. fig. 4 a), whereas it is barely in- 

 dicated in T. robusta (Plate V. fig. 3 a). There are two prominent 

 muscular tuberosities about midshaft in T. Spratti. 



The anterior aspects in both are more concave than appears to be 

 the case in the recent species named above ; and there is greater 

 dilatation at the articular surfaces ; otherwise they do not appear to 

 present further characters to distinguish them from the tibiae of 

 recent species and from one another. 



Fibula. 



The distal half of a left fibula from Zebbug represents a tortoise 

 considerably larger than the owner of the tibia, PlateV. fig. 3, but not 

 apparently of greater dimensions than the individuals to which the 

 large femora and coracoid belonged. The tarsal articular surface is 

 trihedral in outline and somewhat convex, whereas it is even in T. 

 ephippium. There is the usual expansion of the articulation as seen 



