THE OLDEST AIR-BREATHERS 285 



been the young of some larger reptile, too large and vigorous 

 to be entrapped in the pitfalls presented by the hollow Sigil- 

 laria stumps, and in its adult state losing the batrachian pecu- 

 liarities apparent in the young. Whichever of these views we 

 may adopt, the fact remains, that in the structure of this curi- 

 ous little creature we have peculiarities both batrachian and 

 lacertian, in so far as our experience of modern animals is 

 concerned. It would, however, accord with observed facts in 

 relation to other groups of extinct animals, that the primitive 

 Batrachians of the coal period should embrace in their struc- 

 tures points in after times restricted to the true reptiles. On 

 the other hand, it would equally accord with such facts that 

 the first-born of Lacertians should lean towards a lower type, by 

 which they may have been preceded. My present impression 

 is, that they may constitute a separate family or order, to which 

 I would give the name of MICROSAURIA, and which may be 

 regarded as allied, on the one hand, to certain of the humbler 

 lizards, as the Gecko or Agama, and, on the other, to the 

 tailed Batrachians. 



It is likely that Hylonomus Lyelli was less aquatic in its 

 habits than Dendrerpeton, Its food consisted, apparently, of 

 insects and similar creatures. The teeth would indicate this, 

 and near its bones there are portions of coprolite, containing 

 remains of insects and myriapods. It probably occasionally 

 fell a prey to Dendrerpeton, as bones, which may have belonged 

 either to young individuals of this species or to its smaller 

 congener H. Wymani, are found in larger coprolites, which 

 may be referred with probability to Dendrerpeton Acadianum. 

 This coprolitic matter, which is somewhat plentiful on some of 

 the surfaces in the erect trees, also informs us that the im- 

 prisoned animals may in some cases have continued to live for 

 some time, feeding on such animals as may have fallen into 

 their place of confinement, which was destined also to be 

 their tomb. Some other points of interest appear on the 



