534 



P.M 



MR, D. W. DEVANESEN ON THE 



Text-figure 4 (A, B, C, D, and E). 

 A 



-S. 



-Na. 



A.H 



A. A dorsal view of the skull of Cacopus systoma. The vestigial condition of the 



squamosal (Sq.) is remarkable. L., ligament connecting the latter with the 

 pro-otic. For other letters consult the key-list of abbreviations. 



B. A ventral view of the same. P., vestigial palatine ; T.F., trigeminal slit. For 



other letters consult the previous text-fig. (A) and the key -list of abbreviations. 



C. A lateral view of the same. L-M., a straight line drawn along the suture between 



the nasals and the fronto-parietals of the cranium. A-B, the plane in which 

 the proximal circumference of the skull lies. C-D, the plane in which the 

 distal one of the same lies. A.H., articular knob for the lower jaw ; Fr.P., 

 fronto-parietals ; Na., nasals. 



D. A lateral view of the skull of Mana liexadactyla. A brief comparison of the 



Cacopus skull with this will reveal the differences mentioned in the text. 

 L.M., the same vertical line mentioned in the previous text-fig. (C). For other 

 letters consult key-list. 



E. Lower jaw of Caco'pus systoma, as seen from below. A., angulosplenial ; M., 



Meckel's cartilage; D., dentary ; M.M., mentomeckelian ; C, cartilaginous 

 portion of the latter. 



