20 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.37. 



As may be seen by referring to the list of measurements, the skull 

 of the present form measures only 6i mm. in length. The form may 

 possibly be larval, though I do not think so, if I may judge from the 

 well-developed condition of the skull bones and the complete ossifica- 

 tion of the vertebra}. The sides of the skull are equal and the base 

 is a straight table, *o that the skull forms almost an exact equilateral 

 triangle. The orbits are very small and are placed well forward. 

 The interorbital space is four times that of the diameter of the orbit, 

 a very unusual character and in itself is almost worth}' of ranking 

 as a generic character. The median suture of the skull is zigzag, 

 and incloses the minute parietal foramen near the posterior end of 

 the skull. The relations of the elements of the skull, with the excep- 

 tion of those of the frontals and parietals, can not be determined Avith 

 accuracy, although there are here and there indications of sutures. 

 The characters exhibited by the cranial elements, so far as they can be 

 determined, are those of the family Tuditanida,', and the form may, 

 for the 2:)resent, be regarded as a member of that group. The teeth 

 are very long, slender, and sharp, and are placed close together. 

 There is no indication of fluting on the teeth. They are slightly 

 curved inward. 



There are thirteen vertebrae prcvsent. The centra are hour-glass 

 shaped, and are apparently phyllospondylous, with the notochord 

 largely persistent. The vertebral centra are unusually long and slen- 

 der, with the ends rounded. The humerus of the right side is pre- 

 served. It it a long, slender bone Avith expanded extremities. There 

 is no evidence of abdominal armature nor of ribs. 



The discovery of this form in the Linton deposits is of consider- 

 able interest as indicating a Avide range in size and character of the 

 fauna of the time. The forms now knoAvn from Linton range fiom 

 the Odo)it<'fpet<)n to the form designated Macrcr-pcton Juixleyi Cope, 

 with a skull possibly 8 inches in length and whose body may have 

 attained some feet in length. The large rib described below un- 

 doubtedly indicates a large form of the ancient Amphibia from 

 Linton, as do the vertebra; described by Marsh in 18G3 from Nova 

 Scotia. 



Mt'dsiirciiKiil.s of the hji)v Odoiilcrpctdn fiiiiiu/iildri.s Moodie. 



« 



I.ength of animal, as preserved IS 



Length of skull 6. 



Posterior width of skull 5. 



Length of side of skull 6, 



Diameter of orbit . 



Interorbital width 2 



I^ength of tooth 



Length of vertebra 1. 



Width of vertebra 



Length of humerus 2. 



Distal width of humerus 



1 



