272 Reviews — Br. Anton Fritsch — 



head and a short tail. The skull is triangular, and rounded in front. 

 The teeth in the preinaxillary bone are larger than those in the maxil- 

 lary ; they are smooth, and have large pulp cavities. All the palatal 

 bones are strongly denticulated. The only species known is Seeleya 

 pnsilla. Like the preceding type, it is covered with thin oval scales, 

 which are dichotomously ribbed. 



Only the under side of the skull is exposed. There are four large 

 slender smooth teeth in the premaxillary. In the maxillary bone 

 there are 10 or 12 teeth. In the lower jaw 18 teeth are seen in the 

 dentary bone. The vomer carries many small teeth. The para- 

 sphenoid hos a slender anterior spine and a small posterior quadrate 

 shield. Triangular bony plates tapering anteriorly lie on each side 

 of the spine of the pai'asphenoid, and fill in the space between that 

 bone and the curved pterygoid. This plate, which carries scattered 

 teeth like those on the pterygoid, is regarded by the author as the 

 vomero-palatine. The notochord, which is narrow, terminates ante- 

 riorly beneath the parasphenoid in a fusiform mass, which the author 

 regards as material out of which the basisphenoid is to be developed. 

 But he doubts whether the cranial portion of the notochord may not 

 be in direct connection with the vertebral portion as in bony fishes, 

 since such connection would account for the circumstance that he 

 has never been able to distinguish the two lateral condyles which 

 are presumed to exist. But it seems to me that if the discontinuous 

 character of the notochord is established, it would tend to show that 

 the segmentation of the protovertebraj in development was not com- 

 plete anteriorly, and that the posterior half of the body of the basi- 

 occipital centrum may perhaps unite with the body of the first 

 vertebra, while the anterior element remains united to the basi- 

 sphenoid portion of the notochord. And if so, the circumstance 

 would help to explain the relatively great development of the exocci- 

 pital bones characteristic of modern amphibians. 



The lower jaw is strongly developed and runs the entire length of 

 the skull. There are slight indications of branchial arches. 



There are 60 vertebrae ; of which 33 belong to the trunk, and 27 

 to the tail : they are one and a half times as wide as long. The 

 neural arch extends along the centrum, and has the neural spine 

 extended both in front and behind in a hatchet form. Similar pro- 

 cesses are found in the early caudal vertebrae, but from the fortieth 

 to the fiftieth they become smaller and lose the antero-posterior 

 expansion. The first 20 ribs are about four times as long as the 

 vertebrae, moderately curved, and have capitulum and tuberculum 

 equally developed. The later vertebrae become rapidly shorter. In 

 the tail the ribs have but one head. The hinder extremity is one 

 and a half times as long as the fore limb. 



The genus Bicnodon is instituted for a small amphibian with a large 

 head, having the cranial bones pitted, and with strong limbs which 

 are equally developed anteriorly and posteriorly. The parasphenoid 

 and pterygoid are armed with teeth. The scales are large. The genus 

 includes three species, named Bicnodon Copei, B. disperstis, and 

 B. trachylepis, which are associated by the author with some doubt. 



