A LABORATORY OUTLINE OF NEURO-ANATOMY 



THE following directions for the study of the gross and microscopic anatomy of 

 the nervous system are intended to aid the student in making the best use of his time 

 and laboratory material. Free use is made of the sheep's brain because in most in- 

 stitutions the number of human brains available is limited, and these are often poorly 

 preserved and entirely unsuited for dissection. Even if an unlimited supply of well- 

 preserved human brains were at hand, there would still be an advantage in the use of 

 the sheep's brain because in it certain structures (such as the olfactory tracts and centers 

 and the really significant subdivisions of the cerebellum) are more easily seen and more 

 readily understood. 



The outline has been written in such a way that it can be readily adapted by the 

 instructor to meet his own needs. It is assumed that each instructor will furnish his 

 students with a schedule for the laboratory work, showing the number of laboratory 

 periods available and the topics to be covered each period. This will help the student 

 properly to apportion his time and enable the instructor to arrange the order of the 

 laboratory work to his own liking. The paragraphs have been numbered serially in 

 order that in such a schedule they may be referred to by number. It is not necessary 

 that the topics be taken up in their numeric order. And in a course of one hundred 

 hours some of the topics should be omitted altogether. How much should be omitted 

 will depend largely on the amount of drawing required. It is assumed that the in- 

 structor will indicate on the laboratory schedule the drawings which he wishes to have 

 made. For this reason we have, for the most part, omitted specific directions for draw- 

 ings. 



Since it will be necessary for the student in using the outline to make frequent 

 references to figures in the text, it will be convenient to keep in the book several strips 

 of thin paper to serve as bookmarks. 



METHODS OF BRAIN DISSECTION 



Much information concerning the gray masses and fiber tracts of the brain can be 

 obtained by dissection. This should be carried out, for the most part, with blunt 

 instruments. It is rarely necessary to make a cut with a knife. An orangewood mani- 

 cure stick makes an excellent instrument. It should be rounded to a point at one end 

 for teasing, while the larger end should be adapted for scraping away nuclear masses. 

 A pair of blunt tissue forceps of medium size with smooth even edges and fine transverse 

 interlocking ridges is also an essential instrument. This is useful in grasping and strip- 

 ping away small bundles of fibers. In dissecting out a fiber tract it is necessary to have 

 in mind a clear idea of the position and course of the tract, and the dissecting instru- 

 ments should be carried in the direction of the fibers. Where it is necessary to remove 

 nuclear material in order to display fiber bundles, it will be found very helpful to let a 

 stream of water run over the specimen while the dissection is in progress. 



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