140 EDWARD L. RICE 
(prom.s-c.a.) bemg most sharply marked and forming the entire 
anterodorsal border of the rather triangular upper portion of the 
capsule. This prominence is marked off from the rest of the 
capsule by a sharp groove, plainest in its middle course and be- 
coming less definite at the anterior end, where the prominence 
of the canal broadens out into that of its ampulla (prom.amp.a.). 
At the upper angle of the capsule a slight notch separates the 
prominence of the anterior from that of the posterior semicircular 
canal (prom.s-c.p.), which is much less clearly marked than the 
anterior, being limited by a very shallow and rather indefinite 
depression. The prominence of the posterior canal broadens at 
its lower end, forming a conspicuous projection, the prominence 
of the posterior ampulla (prom.amp.p.) By the contact of this 
prominence with the edge of the basal plate the fissura metotica 
is divided, as already noted, into its anterior and posterior parts. 
Posterior and dorsal to the prominence of the anterior ampulla 
is that of the lateral ampulla (prom.amp.l.), and from this the 
prominence of the lateral canal (prom.s-c.l.) extends backward, 
forming the main lateral convexity of the auditory capsule. 
Posteriorly it merges with the prominence of the posterior canal 
above the posterior ampulla. For the most part the prominence 
of the lateral canal is poorly marked, but in its posterior third the 
cartilage is much thickened and forms a conspicuous projection, 
the crista parotica (cr.par.), discussed later in connection with 
the columella auris (p. 155). Immediately below the crista, at 
the beginning of the elongate cochlear prominence (prom.coch.), 
is the large elliptical fenestra vestibuli (fen.vest.), partially filled 
by the footplate of the columella auris (ft.pl.). The prominentia 
saccularis (prom.sac.), bounded by the semicircular canals, and 
the prominentia recessus utriculi (prom.r.ut.), ventral and 
posterior to the anterior ampullar prominence, are as in Lacerta. 
In median view (fig. 8) the prominences of the anterior semi- 
circular canal, anterior ampulla, lateral ampulla, posterior am- 
pulla, and cochlea are again recognizable, although the contours 
are in general less sharply marked than on the outer face and less 
sharply marked than in Lacerta. The middle of this surface of 
