338 Henry L. Bruifer 



planum terminale has no connection either with the posterior or with 

 the lateral wall of the nasal capsule the various fenestrae are not 

 separated laterally i. 



The three blind sacks of the anterior division of the nasal 

 cavity of Rana are separated by cartilaginous septa which are 

 attached to the outer wall of the nasal capsule. Between the cavum 

 medium and the cavum inferius lies the lamina inferior, whose 

 lateral margin joins the side wall of the cavum medium; between 

 the cavum superius and the cavum medium lies the lamina superior. 

 The caudal part of the lamina inferior is united with the anterior 

 angle of the planum terminale; the line of union, however, does not 

 lie in the plane of the cartilaginous lateral wall of the cavum medium 

 but falls farther medial, and is separated therefore from that wall 

 by a short section of the lamina inferior. In the interval between 

 the planum terminale and the lateral wall of the nasal capsule lie 

 the lacrymal duct [D.nl.^ Fig. 12) and the ventral tubules of the 

 glandula nasalis externa [Gl.n.e.^ Fig. 14). 



The bending of the planum terminale into the nasal cavity, as 

 above described, gives rise to an internal prominence, which has 

 been described by Born (5) as a homologue of the turbinal of the 

 salamander. In Rana this turbinal is particularly prominent at its 

 anterior end where, as previously stated, the margin of the planum 

 terminale is strongly incurved (compare Fig. 14, PI. XVIII). 



In the roof of the cavum medium, supported by the lamina 

 superior, the planum terminale and the lateral wall of the nasal 

 capsule, lies a small horseshoe-shaped bone, the intrauasale of Gaupp, 

 [Int7\^ Fig. 14), whose two caudo-medially directed arms are separated 

 by a narrow cleft. The medial arm of the bone lies in close contact 

 with the free margin of the lamina superior; its broader lateral arm 

 extends toward the anterior incurved angle of the planum terminale, 

 embraces with its excavated caudal margin the anterior convex 

 surface of this cartilage (see Fig. 14), and then terminates at the 

 medial margin of the same, that is to say, at the anterior incurved 

 end of the turbinal prominence. Beneath the lateral arm of the 

 intranasale the ductus naso-lacrymalis passes to its opening at the 

 anterior end of the planum terminale. 



The slit-like opening between the two arms of the intranasale 



^ Born states (Morph. Jahrb. Bd. XI. 1870) that in j'oung Bombinator the 

 planum terminale readies the posterior wall of the nasal capsule. 



