DISSECTION OF THE HEAD AND NECK 



355 



Study- 



(1) Medullary body (corpus medullare). 



(2) Medullary laminae (laminae medullares). 



(3) Arbor vitae (arbor vitae) ("tree of life"). 



(4) Cortical substance (substantia corticalis). 



(a) Inner, yellowish or reddish-brown, " granular" layer (stratum 



granulosum). 



(b) Outer gray layer (stratum cinereum). 



(c) Layer of Purkinje's cells between (a) and (b) (stratum gan- 



gliosum ) . 



Transverse section through brain of new-born babe. Level of colliculi inferiores of corpora 



quadrigemina. ( Weigert-Pal, series ii. section No. 290. ) 



Aq.cer., aquaeductus cerebri ; a, fibres running from lateral lemniscus toward dorsal border of 

 brachium conjunctivum ; Br.Conj., brachium conjunctivum; C.c.L, commissure between the colliculi 

 inferiores; Dec.Bech., ventral portion of brachium conjunctivum, which in reality forms a commissure 

 between the superior nuclei of the vestibular nerves of the two sides; F.l.m., fasciculus longitudinalis 

 medialis ; F.Py., fasciculi longitudinales pontis (pyramidales) ; L.I., lemniscus lateralis in large part 

 terminating in the nucleus of the colliculus inferior ; L.m., lemniscus medialis; N.IV., N. trochlearis ; 

 Nu.Coll.inf., nucleus colliculi inferioris ; Fu.c.s.(l), nucleus centralis superior, pars lateralis ; Nu.c.8.(m), 

 nucleus centralis superior, pars medialis; R.d.n.V., radix descendens [mesencephalica] N. trigemini; 

 St.gr.c., stratum griseum centrale. (From Barker, The Nerv. Syst., New York, 1899, p. 485, Fig. 315.) 



Make a frontal section through the left half of the cerebellum 

 at about its middle (cf. Spalteholz, Fig. 743), and a horizontal 

 section through the right half of the cerebellum in the general 



