N.e6 



Pig, 227. — Diagrammatic figure of a Human Embryo, lettered by Professor 

 His, Ko, and estimated as thirty-one days old. The brain and spinal 

 cord, and the cranial and spinal nerves are shown, and certain of the other 

 organs are represented in outline. The bases of the fore and hind limbs 

 are indicated by the dotted outlines. In all oases in which the full length 

 of the nerve is not shown, the end is represented as though cut across. 

 (After .His.) x 10. 



BF, thalamencephalon. BM, mid-braiu. BS, cerebral hemisphere. BY, olfactory 

 lobe. EI, auditory vesicle. PGr, Eroriep's gauglion. GO, ciliary gaugUon. HM, 

 byomandibular cleft, or external auditory meatus. If.l, ganglion of first cervical nerve, 

 lg.9, gauglion of first thoracic nerve. 1S.21, ganglion of first lumbar nerve. 1^.26, 

 gauglion of fli-st sacral nerve. IT. 31, ganglion of first coccygeal nerve. ITH, pbi-enio 

 nerve. OC, optic cup. OP, olfactory pit. RB, left auricle. RV, ventricle. SIT, 

 sinus praecervioalis, TI, vitelline loop of intestine. TL, tail. W, Uver. Ill, third 

 cranial nerve. IV, fourth cranial nerve. "V", G-asserian ganglion. "Va, ophthalmic 

 branch of fifth, or trigeminal nerve. V&, maxUlary branch of fifth, or trigeminal nerve. 

 Vc, mandibular branch of fifth, or trigeminal uerve. VII, ganglion of the seventh, or 

 facial nerve. VIII, ganglion of the eighth, or auditory nerve. IX, ninth, or glosso- 

 pharyngeal nerve. X, ganglion of the root of the tenth, or pneumogastrio nerve. XI, 

 roots of the eleventh, or spinal accessory nerve. XII, roots of the twelfth, or hypoglossal 

 nerve. 



M M 



