038 DU. J. \V. DAWSON' ON' KUKCT THKKS CONTAI.VINO ANIMAL 



in 1 millimi'trv; niiti'iinr in.iiiililiular ttu'th Hotnowliit Iiir;;t'r tluiii tlio otliiTs, an<l hoiifc 

 or liodlvi'd. A'diiiiT oi' |i;il;itt' with iiiimiti! ti'otli. Tlionicio pliuo Iiirj^c. Scales of 

 alxldiiK'ii nval, l)iit soimwliat narrow, ami ti'tidiiig to be oat-sliapt'd. 



L(M)!,'tli of" niaiidililr (iiii|ifrl'frt^ ....'.( iiiilliim'tics. 

 ,, llUIIM Ills 7 „ 



vnttlira 2 ,, 



til.ia (.') f) 



li 'iiacic |i!ati' TJ ftMitiiiU'tiV. 



six L'aiidal vcrtflinu 8 luilliiiiL'trey. 



5. Siitller2>floii ncirtlruUttiim, Dawson (I'lato 40, fiys. 28 to 45). 



[irif/onoiii'is (ii'!(<Ir)i((itiis,])\., jMiiiiial of Cio< .logical Society, I.e. ' Air-biviitliers of 

 tlic Coal PciiiKJ,' |i, lit. 'Acadian (icoloLr.v,' \t. :]7(\.] 



This animal was ori!,fiiially rt'i'cncd l)y nic to the "■cniis Ifi/li'innit'i.'i; hut additional 

 specnnens and iiKire carel'ii! comiiarisoii uhlij^e nu' to place it in a new <,'eiius. 



Its most reinarkal)le distinct ion is the form of the niandiluilar and maxillary teeth, 

 which are of a peculiar wcd-v-shape, hein^i-- l)i'oad and oval at ha.se and narrowed to a 

 lonoitudinal edge at top. Tims, when viewed from the .side they appear narrow and 

 blunt, hut when tlii' jaw is broken across, ami they are viewed from the rear or front, 

 they appear broad and sharp-cdnvd. The ell'ect of this arran,i,'onient is that the jaw is 

 armed with a ciosdy-placed series of chisels dv wed^j^es, jxiviiiir i,ii almost continuous 

 edge. At the end of the mandible some of the teeth are longer and more conical. 



Another important character is that the palatal and vomerine bones seem to have 

 bristled with teeth, mostly of very small size ; but there are also some larger palattd 

 teeth, of which some are sharply pointed and others blunt with furrowed point.s. 



The vertebiaj ui'e of the same type with those of ILjhniomns; but some Avhieh appear 

 to be caudal have a pointed spine abuve, indicating perhaps a ilattened tail. The ribs 

 are short and stout. 



Ojily a few fragments of tlu^ limbs have been found ; they would seem to have been 

 less .Icveloped than in ]f>//nm»,»,s, and perhaps this animal was less gifted with 

 jM-wers of walking on land than any of the other Mirrosanno. This would accord 

 w.th the fact that its bones are much scattered, and occur chiefly in sandy layers, as if 

 ir.trodueed in tunes of rain or of partial inundation. 



Some fragments indie it( thoiacic plate.s, and there are numerous abdominal scales of 

 oval form. Above, the body appears to have been clothed with small tubercles and 

 lorny scales, and to have had cuticular pendants like those oi' JJriHlrrrprton. 



In a large specimen the mandible mea.sures 2-2 centimetres, the femur 2 centimetres, 

 and a rib the same. The ibilowing are measurements from a smaller specimen :— 



