SYKONTJfS AND REFERENCES. 483 



§ 1273. Pero (ol facto ri us), po.—V\. IV, Fig. IG ; § 1139. Meynert (Strieker, A, Fig. 

 261). 



This name was proposed by the senior author (,9, 135) for the softer ectal layer of the 

 Ldbus olfactorlus from which the olfactory nerves arise. The word signifies a kind of 

 boot made of raw hide, and seems more appropriate than the term Bulhus olfactm'ius 

 used by Meynert (Strieker, A, 671). 



§ 1274 Pes (olfactorius), ps. ol.—P\. IV, Fig. 16; § 1139. Meynert (Strieker, A, 

 Fig. 261). 



This name was proposed by the senior author {i), 1C6 ; 14, 538) for the ental and 

 fibrous portion of the Lobus olfactorius. It is in harmony with the term crus, already in 

 use, and with pero, which was proposed at the same time, and less apt to be misunderstood 

 than the term Lobus ol. used in this restricted sense by Meynert (Strieker, A, 671). 



§ 1275. Pia (mater), _pi.— Fig. Ill, 112, 121-123; § 1078. Gray, A, 609 ; Quain, A, 

 II, 571. 



8yn. — Meninx vaseulosa, membraua vaseulosa, membrana tenuis. 



The immediate envelope of the myelencephalon, dipping into the fissures and sup- 

 porting the vessels. Its relations to the teljB and plexuses are not fully understood. 



§ 1276. Pons (Varolii), (az.), pn.—Fig. 116, 118 ; PI. II, Fig. 3, 4 ; PI. Ill, Fig. 9, U. 

 Gray, A, 610 ; Quain, A, II, 511, 756. 



Syn. — Pons eerebelli, tuber annulare, protuberantia basilaris. 



The bridge-like mass upon the basis encephali connecting the two sides of the cerebel- 

 lum. It forms a prominent landmark of the mammalian brain, and is not present with 

 the lower vertebrates. 



§ 1277. Porta, p.— Fig. 110-113, 120, 123 ; PI. Ill, Fig. 13 ; PI. IV, Fig. 14, 16, 18, 19 ; 

 § 1065. Gray, A, 630 ; Quain, A, II, 544. 



Syn. — Foramen Monroi, lateral orifice of the y-shaped Foramen Monroi. 



This more or less constricted communication between the aula and the procoelia is 

 described in connection with the figures above named and in §§ 1006, 1145, 1151. The 

 reasons for adopting the single word in place of the compound term have been given by 

 the senior author (3). 



§ 1278. Portio depressa (praeperf orati ), Pt. d. — The caudal and depressed portion of 

 the (Locus) prgeperforatus, which see (§ 1293). 



§ 1279. Portio diencephalica (Cruris cerebri), Pt. den.— Fig. 116, 118 ; PI. Ill, Fig 9, 

 11; g 1142. 



In the cat the Crus cerebri is traversed by the cimbia, and its ventral surface is sepa- 

 rated thereby into a caudal or mesencephalic portion and a cephalic or diencephalic. The 

 latter presents a longitudinal ridge, mesad of which is the quadrans, while the postgenicn- 

 latum lies just laterad of it. 



§1280. Portio mesencephalica (Cruris cerebri), Pt. msen. — Fig. 116, 118; PI. II, 

 Fig. 3 ; PL III. Fig. 11 ; § 1142. 



This is the part of the crus which is visible upon the undissected brain between the 

 pons and the hemisphere. See Crus cerebri (§ 1215), cimbia (§ 1203), and Portio dience- 

 phalica (§ 1279). 



§ 1281. Portio prominens (praeperforati), Pt. /7.^The cephalic, elevated and usually 

 furrowed portion of the (Locus) praeperforatus, which see (§ 1293). 



§ 1282. Portiplexus. iij9.r -Fig. 113, 123. 



This name was proposed by the senior author (f>, 136) for that small portion of the 

 plexus which hangs in the porta. 



