246 F. n. EDOEAVORTH. 



ginosus, and Pelobates.^ In Eana, at the end of the meta- 

 morphosis, the transversi ventrales II and III disappear, 

 wliilst trans versus ventral is IV persists. 



Wilder was of opinion that transversus ventralis IV 

 (constrictor laryngis, hyopharyngeus of Goppert, Veren- 

 gerer des Aditus laryngis of Henle) was a derivative of the 

 intrinsic ring, i.e. of the sphincter laryngis. Goppert, on 

 the other hand, thought that it was homologous with the 

 hyopharyngeus of Urodela, only differing in that it fails 

 in the larva to be attached to the fourth bar. This homology 

 of Goppert is confirmed by the development of the muscles. 

 In the Anurau larva3 examined the muscle was attached to 

 the fonrth bar. 



The Anlagen of the interarcuales ventrales develop into 

 longitudinal muscles, each extendiug from the bar of its 

 segment of origin to the next anterior one. In 9 mm. larvae 

 the interarcualis ventralis I s. branchio-hyoideus divides 

 longitudinally into two parts, one of whicli connects the first 

 branchial bar to the cei-atohyal, the other forms with the 

 interarcualis ventralis II a muscle extending from the second 

 branchial bar to the ceratohyal. A similar development of 

 the interarcualis ventralis I takes place in Bufo lenti- 

 ginosus, Alytes, and Pelobates." 



The Mm. marginales of Alytes, Bufo, Eana, and Pelobates 

 (vide Schultze), run along the external edges of the corres- 

 ponding branchial bars ; their dorsal ends are attached to the 

 external surf aces of the upper ends (below the insertions of the 

 levators) of their respective bars. The ventral end of the first 

 is attached to the second bar — to the processus branchialisof 

 Schultze, which is formed from the second bar, the ventral 



' The transversi ventniles II and III are collectively termed '• basi- 

 hyobrancliialis " by Schultze, in Pelobates. 



2 Schultze did not describe the mnscle passing from the first 

 branchial bar to the ceratohyal in older larva; of Pelobates, but it per- 

 sists up to the stage of 'SO mm. The interarcuales II and III he 

 collectively terms the " interbriuichiul " ; and the muscle passing from 

 the second bar to the ceratohyal the " cerato-hyo-brauchialis." 



