OF THE TONGUE OE PARliOTS. 225 



sends forwards a small muscular tract which becomes confluent with the outer border 



of the right hypoglossus rectus, very similar to that in Stringops (PI. XXVIII. fig. 26), 



but differing from it in its partial separation from the parent muscle and in its greater 



size. The fibres of the ceratoglossus inferior posticus are sagittally arranged, the 



tendon extending backwards for some distance between the two rows of converging 



fibres ; the sagittal arrangement is very similar to that of the ceratoglossus inferior 



posticus dorsalis of Pezojwrus (PL XXIX. fig. 47, (3, & text-fig. 4, p. 22-3). 



Were the inner row of fibres to lose its connection with the tendon and to become 



attached by its anterior extremity to the posterior margin of the basihyal, the muscle 



would repeat the condition exhibited by that of the left-hand side in Brotogerys and 



Psittiiius, assuming that, coincidently with the separation from the tendon, the fibres 



slightly altered their direction. 



In Pi/rrhulopsis personata the muscle is similar to that in P. splendens, but the 



ceratoglossus inferior anticus is the same on both sides, resembling the right-hand one 



of the latter bird, but not possessing the anterior extension to the hypoglossus ; and 



the fibres of the posterior ceratoglossus are not so markedly sagittate in their 



arrangement. 



Stage 8. 



As in the lower stage (7) the ventral fascia of the ceratoglossus inferior anticus is 

 not tendinous, but the tendon is much more strongly developed and extends farther 

 posteriorly along the ceratoglossus inferior posticus. The latter muscle is always 

 strongly developed and reaches to the posterior extremity of the hypobranchial. The 

 inner portion of the ceratoglossus inferior anticus in two of the three instances 

 examined has undergone complete retrogression (= III). A ceratoglossus inferior 

 anticus accessorius is absent. 



In Lorius domicella (PL XXIX. fig. 37) the fascia of the ceratoglossus inferior 

 posticus [cg.i.]).) at the posterior extremity of the muscle is tendinous, and the muscle 

 itself is not attached, except by connective tissue, along the whole surface of the 

 hypobranchial; the tendinous fascia is thus probably correlated with the loss of power 

 resulting through a reduction of attaching surface. Posteriorly the muscle is merged 

 with the posterior portion of the superior ceratoglossus. The ceratoglossus inferior 

 anticus [cg.i.a.) is relatively small and tends to divide into a ventral inner and a dorsal 

 outer portion ; its inner portion has practically reached stage III in retrogression. In 

 Lorius flavo-palliat'us (PL XXIX. fig. 38) the ceratoglossus inferior anticus does not 

 tend to split into two portions and its inner part has only reached stage II in retro- 

 gression. The ceratoglossus inferior posticus is somewhat stouter than in L. domicella, 

 and the tendon runs back upon its mid-ventral surface for about half its length. In Vini 

 amtralis the muscle is similar to that in Lorius domicella, except that the origin of the 

 ceratoglossus inferior posticus is like that in L. Jlavo-i)alliatus, and the ceratoglossus 

 inferior anticus does not split into two portions. 



