So far as the structure of the skull is concerned, as also the form
of the limb bones, so far as they are recognized, there is nothing


Fic. 2.—Nothedon lentus Marsh. Sacral vertebra, from in front, natural size.
in this genus to differentiate it from Diadectes, and inasmuch as
the name Diadectes has priority of ten days or thereabouts over
Nothodon it must stand, and inasmuch as a family name cannot be
based upon a synonym, if the two names are synonymous the
family designation Diadectidae must have precedence, notwith-
standing the priority of Nothodontidae. If, on the other hand,


REPTILIA: LIMNOSCELIS 23


Nothodon is proven eventually to be a distinct genus from Diadectes,
the family name Nothodontidae Marsh has precedence over Dia-
dectidae Cope.
Diadectes, sp.
In Plate XXXIV, Fig. 8, is given a photograph of an isolated
tooth, showing the root, which I refer somewhat doubtfully to a
small species of this genus. It was found associated with a very
large species of Diadectes in the Craddock bone-bed.
Family Limnoscelidae
Williston, American Journal of Science, XX XI, 380, May, 1911.
Allied to the Diadectidae, but the mandibular and maxillary
teeth are elongate conical, those of the premaxillary very long,
and three in number on each side; skull nearly smooth, elongate,
depressed; no otic emargination; parietal foramen small; a single
sacral vertebra; carpus and tarsus incompletely ossified; no
hyposphene.
LIMNOSCELIS
Williston, American Journal of Science, XXXT, 380, May, 1911.
Limnoscelis paludis Williston, op. cit. supra. New Mexico.
