EXTINCT AMPHIBIA OF NORTH AMERICA 71 
remains of the ventral scutellation and distinguished from the ele- 
ments of the abdominal shield by their size and curvature. They 
were apparently single-headed, but the character of their articulation 
cannot be determined. The ventral scutellation 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 six inches but as they are scattered their exact 
arrangement cannot be determined. They seem to have extended to 
the cloacal region but there are no evidences of the specialized clasp- 
ing organs such as are developed in the ventral armature of O plider- 
peton. 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. ‘The scales are slightly oval, 
tuberculate, and they measure scarcely one millimeter in their longest 
diameter. They show but slight evidences of having been imbricated 
though they may have been so although they may have been inclosed 
in the integument and somewhat separated from each other. The 
most posterior part of the tail preserved seems to indicate that the tip 
was attenuated. It was probably flattened from side to side. We 
may thus regard Ichihyerpeton squamosum as an elongate aquatic 
animal with a long flattened tail, and since there were possibly no 
limbs it would be an animal highly adapted for life in the water. 
The present species is of interest because it represents for the first 
time the discovery of the scaled Amphibia in the deposits of North 
America. % 
MEASUREMENT OF THE Types OF Ichthyerpeton squamosum MOooDIE 
Length of the animal as estimated from the two impres- 
SLOT She ts serie eerie te Cae cei oce ah Wats MN uC CR 3 feet 
Wcengthioilongestampressionecs nel) saeh a6 ec 21 inches 
Length of specimen containing tail impression.......... 9 inches 
Waidth*of:tailtimpression, maximum)....00)0:0- 08... 0252. : 50 mm 
Waidthsoritailfimapression, minimum): a6... as. 255 6 mm 
Wradthrotarsinglerscaleenc aan. acusimuse shuns s eect esas Imm 
Chevron rods in a distance of three mm............... 8 
Distance dtrom"baserortall- tothe tipsa...cceo so.) ss: 125 mm 
Wadthwatebaseotetailere teen coma erwin we ie 08 
