26 THE MYOLOGY OF THE RAVEN. 



the anterior third of the entire length of the ramus, 

 and is carried forward to the posterior margin of the 

 horny covering of the beak, where the latter overlaps 

 the symphysis. Its wonderfully delicate fibres are di- 

 rected transversely to meet those of the muscle coining 

 from the opposite side. The two unite in a mid-longi- 

 tudinal raphe, which as it is produced backwards be- 

 comes faintly tendinous, and is finally inserted as an 

 attenuated aponeurosis into the under side of the hyoid, 

 between the first and second basi branchial, in the middle 

 line (Fig. 17). 



The thin sheet of muscle thus formed spans and 

 stretches completely around the forepart of the inter- 

 ramal space, and by its contraction the tongue is lifted 

 upwards against the roof of the mouth. 



This muscle is well developed in other classes of 

 animals. Professor Mivart found it very large in Mcno- 

 poma, and it varies considerably among the higher 

 Mammalia, 



22. The stylo-liyoideus is the name used by Professor 

 Owen for a muscle which is quite conspicuous in the 

 Kaven. Its origin and insertion are well shown in Fig. 

 7, where the lingual apparatus is drawn down by the 

 dissecting chains, in order to put it on the stretch 

 (see various views of the mandible, where it is shown). 



The stylo-hyoideus arises on the outer aspect of the 

 articular enlargement of the mandible, at about the 

 middle point. Its fibres form a rather long, transversely 



hauptsachlich von der ausserlich den M. liventer mandibulce 

 bedeckenden Fascie." 



Having carefully dissected the mylo-hyoideus out in some fifteen 

 specimens of the Raven, it seems but proper that I should say here 

 that my observations upon it agree with those of Owen, and in the 

 form, in question I have thus far failed to detect a posterior mylo- 

 hyoideus (see Owen's Anat. Verts., vol. ii. p. 153). 



