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Nachdruck verboten. 



Description of New Facial Muscles in Anura, 

 with New Observations on the Nasal Muscles of Salamandridae 1 ). 



Read before the Indiana Academy of Science, December 1897. 



By Henry L. Bruner, Ph.D., 

 Irvington, Indiana (Butler College, University of Indianopolis). 



The results of this investigation include: 



1) New observations on the nasal muscles of the salamanders. 

 These muscles, which were described by the writer in the Archiv für 

 Anatomie und Physiologie, 1896 -), consist in some cases of two 

 muscles only (M. dilatator naris and M. constrictor naris). In other 

 forms a third muscle (M. dilatator naris accessorius) is also present. 

 These are smooth muscles, which arise wholly, or in large part, from 

 tbe cartilaginous nasal capsule, or more definitely, from the margins 

 of the fenestra rostralis. 



The relation of the nasal muscles to the external nasal gland 

 renders it highly probable that the contractions of the former produce 

 a discharge of the glandular secretion upon the margin of the ex- 

 ternal nasal opening. The secure closing of the opening is thus 

 facilitated. 



Study of the development of the nasal muscles of the salamander 

 demonstrates the fact that these muscles arise in situ in the mes- 

 enchyma. There is uo migration similar to that of the striated facial 

 muscles of higher vertebrates. 



2) A description of new nasal muscles in Rana. Comparison of 

 the frog and salamander shows that the former possesses a M. dila- 

 tator naris and also a second muscle, probably homologous with the 

 M. constrictor naris. Both of these muscles, however, are degenerate 

 in Rana and they have also undergone a change of, function, so that 

 they play only a very subordinate part in the closing of the external 

 naris. They give tension to certain soft parts against which the 



1. From the Proceedings of the Indiana Academy of Science, 1897. 



J Bruneb, Ein neuer Muskelapparat zum Oeffnen und Schließen 

 der Nasenlöcher bei den Salamandriden. Archiv f. Anat. u. Physiol., 

 1896. 



