SYNONYMS AND REFERENCES. 485 



§ 1292. Praepedunculus, ^rpd.— § 1141. Gray, A, 635: Qualn, A. II, 576. 

 Syn. — Pedunculus cerebelli superior, processus e cerebello ad testim, crus cerebelli 

 superius, testibrachium. 



The praepedunculi extend from the cerebellum to the base of the postoptici, and form 

 the walls of the cephalic and longer part of the epicoella. 



§ 1293. Prseperforatus (Locus), prj)/.— Fig. 116, 118 ; PI. II, Fig. 3 ; PI. Ill, Fig. 11. 

 Gray, A, 621 ; Quaiu, A, II, 536. 



Syn. — Locus perforatus anterior s. anticus, anterior perforated space. 



The irregular area j ust cephalad of the chiasma. In man it is comparatively small, but 

 in the cat it is larger and presents two quite distinct portions, a cephalic which is more 

 or less elevated and often distinctly marked by longitudinal furrows and ridges, and a cau- 

 dal which is smaller, depressed, and smooth excepting for the vascular perforations which 

 characterize the entire area. The two divisions are hence named Portio prominens and 

 Portio depreasa. Between the depressed portions is the slight gray elevation of the terma, 

 forming part of the floor of the Eecessus opticus. 



§ 1294 ProccElia, ^c— Fig. 110-113 ; PI. IV, Fig. 15, 16, 18, 19 ; § 1064. Gray, A, 

 624 ; Quain, A, II, 539. 



Syn. — Ventriculns lateralis, ventriculus tricomis, lativentriculus, first or second ven- 

 tricle. 



The lateral cavity of the prosencephalon, communicating through the porta with the 

 aula and thus with its platetrope, and with the mesal series of coeliae. Cephalad it opens 

 into the rhinocoelia. 



I 1295. Proplexus, prpx.—Tig. 113, 121 ; PI. IV, Fig. 15, 18 ; |§ 1066, 1149. Gray, 

 •A, 627; Quain, A, II, 545. 



Syn. — Plexus choroideus ventriculi lateralis. 



The larger part of this plexus of the procoelia is formed by the intrusion of the velum 

 or of vessels thereof between the fimbria and the Sulcus limitans so as to appear, still cov- 

 ered by endyma, in the medicornu. Its length thus coincides with that of the rima. 



A smaller portion of the proplexus projects laterad into the praecornu, as shown in PI. 

 IV, Fig. 18. 



Respecting the continuity of the endyma upon the proplexus, see Todd (A, III, 704) ; 

 Balfour (A, II, 364, Fig 260, 261) ; Mivart (B, 267) ; Gray (A, 627) ; Quain (A, II, 546). 

 L § 1296. Prosencephalon (az.), pren.—V\g. 110-118 ; PI. I, Fig. 1, 2 ; PI. II, Pig. 8, 4 ; 

 PI. Ill, Pig. 5, 6, 11, 13 ; PI. IV, Fig. 14.-30 ; §§ 1061, 1138, 1145. Gray, A, 111 ; Quain, 

 A, 11, 759. 



Syn. — Cerebrum, hemisphasrae, forebraiu. 



The cavities of the prosencephalon are the avla, the portm and ihepvoccdim. 



§ 1297. Pseudocoelia {az.), p«c.-§§ 1064, 1137 (4), 1162 (2). Gray, A, 627 ; Quain, A, 



II, 543. 



5j,re._Ventriculus quintus, ventriculus septi pellucidi, ventriculus Sylvu, mcisura 



septi, sinus septi pellucidi, fifth ventricle. 



In man the mesal surfaces of the hemispheres between the callosum and fornix are 

 separated by an interval, the " fifth ventricle." In the cat the two hemisepta are in con- 

 tact, and the pseudocoelia- does not exist. 



§ 1298. Pyramis, py.-Fig. 116 ; PI. II, Pig. 3, 4 ; § 1140. Gray, A, 612 ; Quain, A, 



11,504. 

 I- Syn —Corpus pyramidale, prepyramid, ventripyramid, antenor pyramid. 

 *' At the side of the meson, i,ust caudad of the pons and extending a little caudad of the 



