1894.] AJTATOMT OP PALAMEDEA COBKtTTA. 541 



with upper anterior border of biventer maxillae, spreads out on to 

 the skin of sides and ventral surface of throat. 



Platysma myoides. — This is a narrow fleshy muscle arising from 

 the ramus of the mandible just at the angle of the jaw. It spreads 

 out fauwise both anteriorly and posteriorly and is inserted on to 

 the skin between the jaws, meeting the last-mentioned muscle 

 behind. 



Biventer maxiUcp. — It arises from a well-marked area on the 

 squamosal above and behind the ear, contiguous above and behind 

 with the complexus. It is inserted on to the inner side of the 

 angle of the lower jaw. 



Digastric or depressor mandihulce. — This muscle is divided into 

 an outer and inner part. 



Temporal. — This muscle is divided into three external portions, 

 which lie so close together as to form a continuous mass separated 

 only by fibrous septa. An internal portion is quite distinct. 



Pterygoid. — This muscle consists of three parts. Part I., usually 

 present in birds, is absent. Parts II. and III. are weU-marked. 

 Part IV. is not separable. 



The Hyoid Group. 



Mylohyoid anterior. — This muscle is divided into two parts. 

 The posterior is larger and quite free of the hyoid ; the fibres run 

 right across the lower jaw, there being no distinct raphse. They 

 meet the fibres of the platysma myoides behind. The anterior 

 part is much thinner and has a distinct raphe. It is attached to 

 the front end of the hyoid. 



Mylohyoid posterior. — It springs tendinously from the lower 

 posterior margin of the quadrate and from the posterior outer 

 surface of the angle of the jaw ; it at once divides in two. The 

 posterior smaller portion has been already described as platysma 

 myoides. The anterior part is a broad mass of muscle (stylohyoid), 

 which runs to be inserted along the cornu of the hyoid, reaching 

 as far as just under the mylohyoid anterior and meeting its fellow 

 of the other side. 



Geniohyoid. — This muscle springs from the inner side of the 

 jaw just behind the anterior mylohyoid; it passes dorsally to 

 posterior mylohyoid. It is wrapped round the thyrohyoid bone 

 to the very end. The texture of the muscle is somewhat coarse. 



The genioglossus is entirely absent. 



Ceratoglossus^. — This muscle is divided into two parts. The 

 first part arises from the side of the os entoglossum by a fleshy 

 belly which meets its fellow in the middle ventral line. It is 

 inserted by a long tendon to the tip of the tongue. 



The second part arises fleshy from the upper and outer side of 



' This is in accordance with Gadow's description of the muscle, but in fig. 33 

 of plate xxxii. of his volume in Bronn's ' Klass. u. Ordn.' he letters it cerato- 

 hyoid. 



