136 THE COAL MEASURES AMPHIBIA OF NORTH AMERICA. 



mal covering, which consists of small scales such as Huxley described in the form 

 from Ireland. The specific characters of this form are the small size of the rounded 

 scales, the attenuated tail, the apparent absence of limbs, the character of the ven- 

 tral scutellation, and the slightly curved condition of the ribs. 



It is estimated, from the portions preserved, that the animal attained a length 

 of not less than 3 feet and its body was long and slender. It may have had an 

 appearance similar to the modern caudate genus Siren, though there were doubtless 

 4 limbs present instead of 2. The slendemess of the body is at variance with the con- 

 dition found in the type species Ichthyerpeton bradleyce Huxley, in which the trunk 

 was rather stoutly built. The character of the anterior portion of the body in the 

 present species can not be determined and the skull is wanting. There are no evi- 

 dences of anterior limbs, although the ventral scutellation preserved would seem to 

 include the pectoral region. No pectoral shields are preserved, nor are there any 

 traces of pelvic girdle or limbs. 



The preserved portions on one block include nearly the entire tail and the pos- 

 terior region of the body, and on the other block the dorsal region of the body and 

 the anterior portion of the tail, so that the two specimens supplement each other 

 in an interesting manner. There are impressions of several vertebrae preserved. 

 They are much the same in character as Huxley has described for the type species 

 (/. bradleyce). They are short and thick and were probably amphicoelous. There 

 are likewise preserved the remains of rather slender recurved ribs mingled in with 

 the remains of the ventral scutellation and distinguished from the elements of the 

 abdominal shield by their size and curvature. They are, apparently, single-headed, 

 but the character of their articulation can not be determined. The ventral scutel- 

 lation consists of fine continuous rods arranged in the regular chevron pattern. 

 They do not seem to be divided into oat-shaped scutes, as is the case with the form 

 described by Huxley. The ventral rods are closely packed for a distance of more 

 than 6 inches, but as they are scattered their exact arrangement can not be deter- 

 mined. They seem to have extended to the cloacal region, but there are no evidences 

 of the specialized clasping organs such as Fritsch (251) has described in the ven- 

 tral scutellae of Ophiderpeton. The scales, which are well preserved on the tail, may 

 have covered the entire body, since there are many scattered scales in the dorsal 

 region of one of the specimens. They are slightly oval, tuberculate, and measure 

 scarcely i mm. in their longest diameter. They show but slight evidences of having 

 been imbricated, though it is likewise possible that they were simply inclosed within 

 the integument, and somewhat separated from one another. The most posterior 

 part of the tail preserved seems to indicate that the tip was attenuated. It was prob- 

 ably flattened from side to side. We may thus regard Ichthyerpeton squamosum as 

 an elongate aquatic animal with a long, flattened tail, and since there were possibly 

 no limbs or very small ones, it would be an animal highly adapted for life in the 

 water. The present species is of interest because it represents an additional dis- 

 covery of the scaled Amphibia in North America. The species previously known 

 from the Linton, Ohio, deposits is Cercariomor phus pani'squamis Cope. Dermal 

 scales have also been observed in specimens of Amphibanms grandiccps Cope and 



