. Carnegie Institution of Washington publication. MORPHOLOGICAL REVISION H5 made out as a thin line in the matrix, which fills the back part of the skull; its relations to the basisphenoid and quadrate are normal. The lower jaws lie in position between the upper jaws and the teeth can not be seen. The articular region is low, and just anterior to this the upper edge rises in a prominent coronoid process. The different bones of the jaws can not be made out, but it is apparent that the dentary takes part in the symphysis. The paratype confirms the points made out in the type. It shows the pteryg
. Carnegie Institution of Washington publication. MORPHOLOGICAL REVISION H5 made out as a thin line in the matrix, which fills the back part of the skull; its relations to the basisphenoid and quadrate are normal. The lower jaws lie in position between the upper jaws and the teeth can not be seen. The articular region is low, and just anterior to this the upper edge rises in a prominent coronoid process. The different bones of the jaws can not be made out, but it is apparent that the dentary takes part in the symphysis. The paratype confirms the points made out in the type. It shows the pterygoids as broad plates, approaching each other in the middle line. If there were any teeth on the pterygoids, they are too small to be seen in the present condition of the specimens. Certain small openings, anterior to the orbit in the type specimen, were considered as antorbital openings, but, as these do not appear in the more perfect paratype, they are probably accidental breaks. The type specimens of Cardiocephalus are not well preserved and it was impossible to recognize the relationship of this genus to Gymnartkrus from the description, but a direct comparison makes it very apparent. Cardiocephalus has, in both specimens, grooves lying on the inner side of the orbits, which seem to be natural and not the result of pressure; also, the pineal foramen is extremely small or absent; because of these struc- tures, which are absent in Gymnartkrus, the latter is retained in a separate genus, although it is recognized that when more than the skull is known the two may have to be united. Gymnarthrus was originally regarded as a reptile, but it may almost as readily be placed among the Amphibia; because of its resemblance to Cardiocephalus it is here placed provisionally in the latter Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly res
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1911
