230 



VASCULAR SYSTEM 



FIG. 285. KECONSTBUCTION OF THE HEAD OF A HUMAN EMBBYO OF 9 MM. LONG. (Mall.) 



The vena cerebralis lateralis is seen to pass on the outer aspect of the posterior cerebral nerve-roots 

 and the auditory vesicle 0. The vein on the mesial aspect of V, the ganglion of the fifth nerve, repre- 

 sents a portion of the primitive jugular. V, Gasserian ganglion; ab, acoustico-facial ganglion; 

 ~0j auditory vesicle; g, glossopharyngeal ; hy, hypoglossal. 



AV 



SLS 



FlG. 286. DlAGKAM OF THE VEINS OF THE HEAD OF AN EMBBYO OF FOTJB WEEKS OLD. 



(After Mall.) 



A CV, anterior cardinal vein; VCL, vena capitis lateralis ; SL 8, superior longitudinal sinus; 

 0V, ophthalmic vein ; V, fifth nerve; AV, auditory vesicle. 



VCP 



FlG. 287. DlAGBAM OF THE VEINS OF THE HEAD OF AN EMBBYO OF FIVE WEEKS OLD. (After Mall.) 



VJ, jugular^ vein ; VCP, vena cerebralis posterior ; VCM, vena cerebralis media; VAC, vena cerebralis 

 anterior; TH torcular Herophili ; OF, ophthalmic vein. Other letters as in fig. 286. 



