SYNONYMS AND REFERENCES. 479 



The name here employed was used by Vlcq d'Azyr (A, PI. XVIII, " 48"), and is given 

 in Dunglison ; it should, we think, be retained, notwithstanding the somewhat unusual 

 use of foramen. 



§ 1236. Foramen conarii {as), Fm. m.—P\. Ill, Fig. 6. 



The interval between the postcommissura and the Commissura habenarum, 



§ 1237. Foramen infundibuli (oa.), Fm. inf.— Fig. 118 ; PI. lU, Fig. 11. 



The orifice left after removal of the hypophysis and infundibulum. 



'-'' § 1238. Fornix (as.), /.-Fig. 117, 122 ; PI. II, Fig. 4; PI. Ill, Fig. 13 ; PI. IV, Fig. 

 14-30 ; §§ 1144, 1172, Gray, A, 627 ; Quain, A, II, 543. 



8yn. — Camara, testudo cerebri. 



A subtriangular fibrous sheet, forming successively the cephalic boundary of the aula 

 and portse, the roof of the aula, ajid part of the fioor of the procoelise. (See § 1457.) 



The form, constitution, direction and relations of the fornix are exceedingly diflBcult to 

 describe, and indeed are not fully understood. The fornix proper includes the following 

 parts : eolumnas, commissura, crista, carina, delta and lyra. The fimbricB are its caudo-lat- 

 eral prolongations to the tips of the hypocampal lobules, while the fibrous fasciculi consti- 

 tuting the columnsB are described as beginning in the thalami, passing ventrad to form a 

 figure-of-eight turn in the albicantia, then passing dorsad just caudad of the praecommissura 

 to form the lateral halves of the " body " of the fornix, which again are continued into the 

 fimbriiB. Between the thicker lateral parts of the body of the fornix is the thin and ill- 

 defined surface known as li/ra. 



The caudal portion of the fornix is in contact with the ventral aspect of the callosum 

 at and for a short distance laterad of the meson, and the two are continuous at the sple- 

 nium. See callosum (§ 1195). 



The feline fornix is proportionally much wider than the human, and may be torn into 

 several bands on each side, as indicated by the v-shaped lines in PI. IV, Pig. 14. 



§ 1239. Genu (az.), g.-Fig. 117 ; PI. II, Fig. 4 ; PI. IV, Fig. 17. Gray, A, 623 ; Qnain, 

 A, II, 538. 



The knee-like cephalic curvature of the callosum, ending in the rostrum. 



% 1240. Habena, 7i.-Fig. 117, 123 ; PI. II, Fig. 4 ; PI. IV, Fig. 16 ; § 1143. Gray, A, 

 630 ; Quain, A, II, 549. 



Syn. — Habenula, pedunculus conarii. 



The ridge along the dorso-mesal aspect of the thalamus ; it may be said to be the dor- 

 sal limit of the mesal surface, as the Sulcus habeuse is the mesal limit of the dorsal surface. 



The habena terminates on the cephalic slope of the thalamus as a more or less distinct 

 tubercle which marks the dorsal limit of the porta ; it joins its platetrope by the Cs. habe- 

 narum, forming the cephalic boundary of the Fm. conarii. 



§ 1241. Hemiseptum (cerebri), Imspt.—Fig. 117 ; PI. IV, Fig. 16. 



This is the lateral half of the septum (lucidum), which see (§ 1315) ; its mesal surface, 

 the Area septaUs, is joined with its platetrope by connective tissue (§ 1137, 4). 

 H § 1242. Hemisphaera, hem.— Fig. 104, 110-118, 124, 125 ; PI. I, Fig. 1, 3 ; PI. II, Fig. 

 ' ' 3, 4 ; PI. Ill, Fig. 5, 6, 11, 13 ; PI. IV, Fig. 14-20. 



gyji^ Ganglion hemisphaericum, hemicerebrum, lobus prosencephalicus. 



The lateral half of the largest portion of the brain, united with its platetrope by the 

 fornix, callosum and prascommissura. Its cavity is the procoelia, and the striatum, hypo- 

 campa', and (in man and monkeys) calcar are thickenings or involutions of the parietes. 

 The surface is convoluted, presenting fissurae and gyri. The cinerea is mostly near the 

 surface forming the cortex cerebri. See cerebrum, § 120J. 



