THE MICROSAURIAN FAMILY TUDITANIDyE. IOQ 



The specimen is about half the size of the type. The palate of the skull is well 

 preserved and is extremely interesting. The sutures separating the various palatal 

 elements are not distinct. The parasphenoid is especially large and the exoccipitals 

 are partly ossified, if we may judge by the projecting condyles. Anteriorly the 

 parasphenoid contracts and then expands and on each side of the expanded part lie 

 fragments of the palatines. To the right of the posterior end of the parasphenoid 

 lies a portion of the dorsal element showing the cranial sculpture. 



The left mandible is somewhat displaced to the right of the skull, and crushed 

 and weathered to such an extent that the sutures are entirely obliterated. There 

 are 3 teeth, with indications of others. They are typically pleurodont and sharp 

 and slender. The mandible tapers somewhat anteriorly and at the tip bears an 

 elongate enlarged tooth. 



MEASUREMENTS OF THE THIRD SPECIMEN OF ERPETOSAURUS ACUTIROSTRIS MOODIE IN THE AMERICAN 



MUSEUM OF NATURAL HISTORY. 



mm. mm. 



Length of skull, as preserved 25 Length of mandible 25 



Posterior width of skull 15 Anterior width of mandible 2 



Anterior width of skull 10 Length of large tooth I 



Width across occipital condyles 4 



Erpetosaurus tuberculatus Moodie. 

 MOODIE, Bull. Amer. Mus. Nat. Hist., xxvi, pp. 348-349, pi. Iviii, 1909. 



Type: Specimen Nos. 8693 G and 8610 G, American Museum of Natural His- 

 tory. 



Horizon and locality: Linton, Ohio, Coal Measures. 



This species is based on a fragmentary cranium (plate 26, fig. i) consisting of the 

 posterior part of the right side of the skull. Its association in the genus is solely on 

 the character of the sculpturing of the cranial elements. It is most closely related, 

 in the characters preserved, to the form described by Cope as Tuditanus radiatus, 

 from which it differs especially in the character of the sculpture and in the position 

 of the orbits, as well as the arrangement and size of the various cranial elements, so 

 far as these elements can be detected in the present specimen. In Erpetosaurus radi- 

 atus the skull is sculptured by radiating grooves and ridges which did not arise from 

 a definite center. In E. tuberculatus this center of radiation is marked by an eleva- 

 tion or tubercle on each cranial element exposed, from which the grooves and ridges 

 radiate outward. These tubercles have an elevation of 4 mm. above the cranial 

 element proper. The orbit is located near the median line of the skull, so far as can 

 be determined. In E. radiatus Cope the orbits are located well forward. In that 

 species also the postparietal is smaller than in the present species and the squamosal 

 is longer and more slender. (Plate 25, fig. i.) 



The fragment of a skull on which the above comparison has been made consists 

 of the right postparietal, a portion of the tabulare, the parietal, the frontal, and a 

 portion of the squamosal. The other elements are not clear. The elements in the 

 median line are elongate, as in Erpetosaurus radiatus. The pineal foramen is located 

 well back on the median line and lies posterior to two-thirds of the length of the 



