44 



200. Model showing the head and neck in vertical 

 section. 



.From the Pedagogical Museum, St. Petersburg. 

 E. 663. 1877. 



The larynx is movable ; the model does not aim at giving 

 minute details. 



201. Model of the brain. 



E. 12. 1862. Made by the late Dr. Auzoux, Paris. 



The upper half of each hemisphere is movable to show the 

 upper surface of the corpus callosum. On the left side a portion 

 of the side wall can be taken out to expose, first, the fibres of 

 the corpus callosum, and after removal of these the cavity of 

 the lateral ventricle, with its corpus striaturn and hippocampus 

 minor. The temporo-sphenoidal lobe can be removed to show 

 the end of this latter as well as the optic tract. The under part 

 of the frontal lobe lifts on a hinge and renders visible the 

 fibres forming the pillars of the fornix. The two hemispheres 

 can be separated so as to exhibit the interior of the third 

 ventricle, the septum lucid um, the pineal body, and the optic 

 thalamus. On the left side this last, with the fornix, corpus 

 striatum, choroid plexus, and corpus albicans, is also seen by 

 lifting off another layer of the model. The middle part of the 

 fornix lifts to show the smooth surface of the optic thalamus 

 below it. On this side, moreover, the lower part of the 

 temporo-sphenoidal lobe can be removed to show the hippo- 

 campus major and the corpus fimbriatum. The cerebellum on 

 being removed exposes the fourth ventricle, and it is provided 

 with a median section, to show the arbor vitse and a section 

 through its left lobe. A portion of the pons Varolii has been 

 removed on the right side to show the fibres passing up to the 

 cerebrum. On the back of the medulla oblongata two pieces 

 are loose to show its internal structure. 



202. Model to show the form and relations of the 

 dura mater, enlarged. 



E. 13. 1862. Made by the late Dr. Auzoux, Paris. 



On the left side the wall of the skull is retained in the lower 

 part ; above it is the dura mater which lines the vault of the 

 skull. In the middle line is the superior longitudinal sinus 

 which has been opened to show the contained trabeculaa On 

 the right side a large window has been made to show the 

 form of the cavity and the receptacles for the various parts of 

 the brain. The upper part of the dura mater and the falx 

 cerebri lift off, leaving the tentorium cerebelli, which can be 

 removed in its turn, to show the cavity for the cerebellum. 



