NO. I THE OLDEST KNOWN REPTILE — PEABODY 3 



punctulatus. (Moodie's plate description (p. 28) in fact refers to the 

 posterior skeleton as "the type specimen of Isodectes punctulatus," 

 which, of course, it is not.) Later, Williston (1910) and then Case 

 (1911) established the posterior skeleton as a new genus and species, 

 Eosauravus copci Williston. Unfortunately, the European genus 

 Sauravas to which Williston related the posterior skeleton is clearly 

 an amphibian with nectridian vertebrae, so the name Eosauravus is 

 inappropriate morphologically but remains valid taxonomically. 



Romer (1930) restudied the Linton fauna and, in a commendable 

 attempt to reduce the large number of artificial species, referred Cope's 

 posterior skeleton again to the anterior skeleton now designated as 

 Tuditanus punctulatus. The synonymy of Tuditanus with Isodectes 

 had proved to be wrong since the latter genus now appears to be a 

 captorhinomorph (Gregory et al., 1956, p. 2), and the former genus is 

 a microsaur. Romer's decision apparently rested mainly on the im- 

 probability that there might be more than one reptile at Linton, and 

 that there was the distinct possibility that the smaller, less ossified 

 anterior skeleton merely represents a more immature individual than 

 the posterior skeleton. The two specimens were regarded by Romer 

 as reptilian with no recognizable ordinal characters. Later, Romer 

 (1947, p. 300) suggested that the two specimens together represent 

 either a seymouriamorph or cotylosaur on the basis of a stemmed in- 

 terclavicle, seemingly broad-arched vertebrae, and a pes with a pha- 

 langeal formula 2-3-4-5-4. Still later, Romer (1950, p. 641) dis- 

 counted the importance of the stemmed interclavicle and phalangeal 

 formula, and, while noting a presumed high presacral count of verte- 

 brae, long, slender body proportions, apparent lack of caudal chevrons, 

 and long postorbital region of the skull, concluded that Tuditanus 

 punctulatus (based on anterior and posterior skeletons) "is not im- 

 probably a microsaur." This conclusion, undoubtedly influenced by 

 increased understanding of microsaurs, was followed by both Piveteau 

 (1955) and Huene (1956) in their valuable compendia of vertebrate 

 paleontology. Meanwhile, Romer (1956, p. 483) apparently turned 

 once more toward Williston's opinion of the posterior skeleton as 

 shown by the lone entry "[Reptilia] Incertae sedis. PSeymouriamor- 

 pha. f Tuditanus Cope 1874 (Eosauravus Williston 1910)." Thus at 

 present, the posterior skeleton designated as Eosauravus copei by 

 Williston, is in an obscure position both taxonomically and phyloge- 

 netically. The anterior skeleton is best considered a probable micro- 

 saur amphibian under the designation Tuditanus punctulatus. In any 

 case it is difficult to demonstrate distinctive reptilian characteristics in 



