THE MICROSAURIAN FAMILY TUDITANID.^. 93 



articular ends as though the endochondral tissue was well developed. The hume- 

 rus is expanded at the ends and it is larger at the upper than at the lower end. 

 The ulna is expanded at the proximal extremity, but is more attenuated at the distal 

 portion. It is shorter than the humerus by about one-third of its own length. The 

 radius is a mere slender rod of bone and presents well-developed articular ends. It 

 is slightly shorter than the ulna. The carpus is unossified and its position is repre- 

 sented by a blank space. There are phalanges of 4 digits preserved and they are 4 

 in number. The phalangeal elements, like the other bones of the extremity, have 

 the articular surfaces prominent, with the terminal phalanx claw-like. 



There are no ribs nor traces of them preserved, and a conjecture as to their 

 character can not be hazarded, since they are known in but two other species, in 

 which they are slender and curved. There is no evidence of a ventral scutellation, 

 and so far as is at present known this structure is absent from all of the species of 

 the genus, or at least it is weakly developed. 



The ilium is all that is preserved of the pelvis. The bone itself has disappeared 

 and has left a depression which shows this element to have been an elongate rod very 

 similar to that described for Micrerpcton. The sacral vertebra seems to be indicated 

 by a depression between the iliac depressions. 



One hind limb is preserved nearly entire and the greater part of the other is also 

 preserved, although some of the phalanges are disturbed. The femur is slender and 

 more elongate than the humerus. It has well-formed, rounded, articular ends. The 

 tibia presents unusual characters in that its ends are truncate, as though the car- 

 tilage composing its articular surfaces was not so highly calcified as in the other 

 limb bones. It is somewhat expanded at the ends and is throughout its length 

 broader than the femur. The fibula, like the tibia, is a slender rod of bone, although 

 it is somewhat shorter than the tibia. The tarsus is unossified and its position is 

 occupied by a blank space. Portions of both feet are preserved, but only one digit 

 in the right foot is complete. The metatarsals are elongate and -slightly expanded 

 at the ends. There are 4 phalanges present in the complete digit, which possibly 

 represents the fourth. The first digit is wanting, with the only terminal phalanx 

 preserved claw-like. 



MEASUREMENTS OF THE TYPE OF TUDITANUS MINIMUS MOODIE. 



mm. mm. 



Median length of skull 15 Width of scapula, maximum 2.5 



Width of skull at posterior border .16 Length of coracoid (?) 2 



Length of orbit 3.5 Length of humerus. . . 4 



Width of orbit 2 Length of radius and ulna 3 



Interorbital width . . 2.5 Length of metacarpal i 



Length of clavicle 6 Length of ilium 2.5 



Width of clavicle, maximum . . 3.5 Length of femur 4.5 



Length of interclavicle, estimated 5 Length of tibia and fibula 3 



Width of interclavicle 3.5 Length of foot : 3.5 



Length of scapula 3.5 Length of metatarsal 75 



Tuditanus walcotti Moodie. 

 MOODIE, Proc. U. S. Nat. Mus., xxxvii, p. 16, pi. 6, figs. I, 2; pi. 7; 1909. 



Type: Specimen No. 4474, U. S. National Museum. 

 Horizon and locality: Linton, Ohio, Coal Measures. 



