no. 1828. TWO NEW FOSSIL AMPHIBIANS— HOODIE. 431 



be females. Like the Yale specimens the oesophagus is displaced and 

 partially obscured. The creatures undoubtedly fed on small plants 

 and animals much as do our recent salamanders. The alimentary 

 tract is preserved fully extended. 



The impression of the tail is, unfortunately, too imperfect to show 

 traces of the lateral lines. 



Measurements of the specimen of Eumicrerpeton parvum Moodie (Cat. No. 4400, 



U.S.N.M.). 



mm. 



Length of entire animal 45 



Length of skull 6 



Width of skull 9 



Transverse diameter of the orbit 1. 50 



Long diameter of the orbit 2. 25 



Interorbital space 2. 50 



Diameter of pineal foramen 50 



Length of body from back of skull to pelvis 22 



Greatest width of body 9 



Length of tail .' 16 



Width of tail at base 5 



Length of humerus 3 



Length of femur 2. 50 



Length of tibia (fibula?) 1. 75 



Length of stomach 7 



Width of stomach 3 



Length of intestine (estimated) 56 



Width of intestine 1 



AMPHIBAMUS THORACATUS, new species. 



The genus Amphibamus was the first known of the Mazon Creek 

 Amphibia to which Cope, in 1865, ascribed the species grandiceps. 

 It is interesting that the latest discovery of forms from Mazon Creek 

 should be an additional species of this genus. The specimen referred 

 to is No. 4306 of the U. S. National Museum. It formed a part of 

 the Lacoe collection. The fossil is rather poorly preserved, but the 

 remains are present on both halves of the nodule, so that consid- 

 erable has been made out as to its structure. 



The chief diagnostic characters which will at once distinguish 

 the species are, the elongate arm, the large interclavicle, the shape 

 of the vertebra, and the triangular skull. 



The portions of the animal which are preserved are: the impres- 

 sion of the skull with one orbit; the right humerus and radius 

 (ulna ?) ; the interclavicle; the left clavicle; a single vertebral centrum, 

 with portions of others; and traces of the ventral scutellas. These re- 

 mains are so intermingled with fragments of plants that it has been 

 quite difficult to distinguish bone impressions from plants. This 

 has, however, been successfully accomplished by whitening the 

 fossil with ammonium chloride when the texture of the fossils serve 



