226 PROF. H. G. SEELEY ON THE [Mar. 21, 



palate (text-fig. 34, p. 225), which Dr. Schonland numbered 1, 

 the premaxillary bones extend backward in a wedge between 

 the maxillary bones, so that the vomerine teeth are behind the 

 middle of the maxillary teeth. The vomerine teeth, instead of 

 covering the vomera as in P. laticeps, or forming a close-set group 

 as in R. 794, F. curieiceps, diverge backward in two rows from 

 two strong teeth in front separated by a well-marked median 

 groove. There are five or six teeth in each row. Internal to 

 these are parallel shorter rows, which similarly begin with two 

 stronger teeth in front. Further, in the Donnybrook specimen the 

 pterygoid bones separate in an arch (text-fig. 33, p. 224) which is 

 three-fourths of a cii-cle, round which there is a semicircular row of 

 small teeth. But in the Fei-nrocks palate this median vacuity is 

 bordered by a pair of prominent ridges which divei'ge backward 

 in a V-shape, each carrying six or seven teeth. These rows are 

 flanked laterally by parallel rows of teeth, which complete the 

 form of a letter M (text-fig. 34). The lateral rows appear to be 

 upon the palatine bones. 



Text-fie-. 35. 



Outline showing the truncated snout of FrocoJopJion plaf^rJiinns, 

 from Ferurocks. 



The other examples of skulls which have come into my hands 

 from Fernrocks, such as those numbered by Dr. Schonland 2, 12, 

 13, all differ fi^om the Donnybrook specimens in having the pre- 

 orbital region of the skull much wider and flatter above, without 

 any indication of the tapering conical snout which is found in all 

 the described species. This chai'acter (text-fig. 35) may be con- 

 veniently expressed in the name Procolophon platyrldnus for the 

 flat-nosed species, with the region of the nasal bones forming a 

 flattened truncated prolongation of the frontal region, with the 

 postorbital region long and wide. A longer flat preoi'bital region 

 is seen in another skull (text-fig. 36). If referable to Procolophon, 

 it may be named P. sphenorhinus, terminating in a vertical wedge 

 in front. 



