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Description OF New FacrtAn Muscies In ANURA, WITH NEW OBSERVATIONS 
ON THE NAsAt MuscLes oF SALAMANDRIDAE. 
By Henry L. BRUNER. 
[Abstract. ] 
The results of this investigation are presented under three sub-head- 
ings: 
1. New observations on the nasal muscles of the salamanders. These 
muscles, which were described by the writer in the Archiv fiir Anatomie 
und Physiologie, 1896, consist in some cases of two muscles only (a M. 
dilatator naris and a M. constrictor naris). In other forms a third muscle 
(WM. dilatator naris accessorius) is also present. These are smooth muscles, 
which arise wholly, or in large part, from the 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 external nasal opening. 
The secure closing of the opening is thus facilitated. 
Study of the development of the nasal muscles of the salamander dem- 
onstrates the fact that these muscles arise in situ in the mesenchyma. 
There is no 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. dilatator 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. 
The development of these nasal muscles agrees with that of the nasal 
muscles of the salamander. 
3. Description of a new muscle in the upper lip of Anura. This imus- 
cle, which I hame Musculus labialis superior, lies in the soft overhanging 
upper lip, and has been observed in Rana, Bombinator, Hyla, Bufo and 
Alytes. 
The M. labiaiis superior is composed of smooth fibres. 
