304 THE SALAMANDER 



It is the fenestra narina (Stadtmiiller) or fenestra rostro-nasalis 

 (Bruner) (PI XXIV, fig. 82). 



TheM. constrictor naris (m.c.n.) (Bruner) bounds the posterior edge 

 of the narial opening for rather more than a semicircle, its ends being 

 inserted on the anterior wall of the fenestra on the cart, cupullaris. 



The M. dilatator naris (m.d.n.) (Bruner) arises from the posterior 

 border of the fenestra narina, i.e. from the cart, retro-narina, and 

 passes directly forwards to the posterior border of the external naris, 

 deep to the constrictor muscle. It is inserted on the cutaneous wall 

 of the narial opening. 



M. dilatator naris accessorius (m.d.n'.) (Bruner) is an obliquely 

 directed muscle. It arises from the lateral border of the fenestra 

 narina, partly from the cartilage and partly from the maxilla. The 

 muscle passes obliquely antero-mesially and is inserted in the postero- 

 lateral margin of the narial opening, deep to, and amongst, the lateral 

 fibres of the M. constrictor naris. 



In his later paper (1901) Bruner further showed that the relation 

 of the nasal muscles to the nasal gland, the glandula nasalis externa^ 

 is such as to force the secretion from the gland simultaneously with 

 the closing of the nasal opening. He also showed that they arise in 

 situ from the mesoderm and are not derived from any other muscles. 



The internal nares are large and unprotected by valves. 



The glands of the nasal capsule may be reckoned as consisting of 

 two masses, one external and one internal. The glandula nasalis 

 externa has already been mentioned. It is situated above the sinus 

 lateralis nasi within the fenestra narina in close proximity to the 

 external naris, and to the opening of the ductus naso-lacrimalis into 

 the nasal capsule (d.nas-lc). As described above it is compressed by 

 the M. constrictor naris, so that its function would seem to be that 

 of keeping the edges of the external narial opening moist. The 

 glandula nasalis interna practically envelops the cavum nasi, and lies 

 entirely within the nasal capsule. Its function is to keep the olfactory 

 epithelium moist. As mentioned above Seydel distinguishes the 

 ventral portion as Jacobsons ^ 



BIBLIOGRAPHY OF SECTION XI 



2,5.6,13,14,15,18,25,34,87,88,89,91,134,139,140,152,174,177,178, 

 216, 223, 243, 244, 245, 251, 287, 294, 295, 297, 310, 311, 313, 338, 339, 

 345, 352, 372, 374, 376, 377. 3^©, 397> 40i, 405, 409, 4^5, 422, 423, 439, 

 443. 455, 482, 483, 485, 490, 491, 509, 515, 533> 534, 535, 53^, 573. 574. 

 575, 576, 577. 582, 604, 605, 613, 650, 680, 685, 699, 700, 733, 741, 745, 

 772,795,804,831,838. 



