EXPLAXATIOX OF PLATE XII 



Restoration of the jiiw muscles of Eryoiis. repieseiitiug the Temuosi»ondyli. aiiii 

 (»f Lahklosauius, representing the Cotylosauria 



Fig. 1. — KriioitH. Superficial muscles. 



Very probably the jaw muscles of this foi-m were fundamentally siniilai- to 

 tiiose of modern amphibians and include superficial, middle and deep la,\i>rs of 

 the capiti-maudibularis (Cm.). The pterygoideus anterior (Pt.aiii.) very 

 prt)bably had the normal course and crossed the capiti-mandibularis on the 

 inner side. The jaw was doubtless depressed by the depressor mandibuhe 

 (D.m.) lying behind the quadrate. 



Fi(is. 2-4. — L<ibi(i0!s(uumi. 



As in the Temnospondyli (Fig. 1) the jaw muscles were entirely beneath the 

 dermal skull I'oof. The capiti-mandiltularis was probably differentiated into 

 three layers and was inserted into the Meckelian fossa of the mandible, and 

 the pterygoideus anterior ])robably ci-ossed beneath these, being inserted on the 

 back of the mandible. 



a ng. ;= angular d. =dentary 



art. =^ articular pa. = prearticnlar 



coi'. = coronoid sp. =^spleiiin1 



