. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 314 Bulletin Museum of Comparative Zoology, Vol. 139, No. 6 species, except for E. anthracinus, are more elongated and megophryine in these char- acters. E. anthracinus also shows the triple frontoparietal emargination of E. guthriei, but in squamosal shape there is close agree- ment between E. guthriei and the middle Eocene E. hinschei from the Geiseltal. In both of the latter, the anterior maxillary process of the squamosal is more expanded than the tympanic process, which is narrow and forms a wide, laterally visib
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 314 Bulletin Museum of Comparative Zoology, Vol. 139, No. 6 species, except for E. anthracinus, are more elongated and megophryine in these char- acters. E. anthracinus also shows the triple frontoparietal emargination of E. guthriei, but in squamosal shape there is close agree- ment between E. guthriei and the middle Eocene E. hinschei from the Geiseltal. In both of the latter, the anterior maxillary process of the squamosal is more expanded than the tympanic process, which is narrow and forms a wide, laterally visible roof to this part of the tympanic cavity. This roof lacks dermal sculpture (Fig. 20b, d, R). In dorsal view, E. guthriei resembles Scaphio- pus and E. grandis in the excavation of the posterior border of the otoccipital and squamosal (Fig. 15). The ethmoid of E. guthriei is incomplete and poorly preserved anteriorly but seems to resemble that of E. bayeri and (so far as can be seen in the crushed material) E. hinschei; it is relatively shorter as a result of the less elongate skull of the American form. The vomer has a broad, flat process on the posterior border of the choana as in Leptobrachium hasselti, the most primitive megophryine (Inger, 1966, p. 21) rather than a short, pointed process as in Megophrys. E. grandis has a similar proc- ess to E. guthriei, but it is relatively smaller and closer to the Megophrys con- dition. The occiput of E. guthriei is quite pelo- batine in its well-ossified paroccipital proc- esses and tubera, its general proportions and relatively simple stapes. Unfortunately, the occiput is not known in any other specimen of Eopelobates. Comparison of Figures 12, 13, and 17-23 shows that, in combination, squamosal and frontoparietal shape distinguish the modern pelobatid species. Since the specific status of the latter is based on many other criteria not available in fossils, these characters can be confidently applied to fossil samples. Either chara
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