4i8 



Scientific Proceedings (124). 



of the fresh organ from formalin material, without the necessity 

 of having delicate balances at the autopsy and without delaying 

 fixation. 



To avoid injury to the posterior lobe, it is safer to remove the 

 entire sella turcica with the pituitary in situ by pinching off the 

 clinoid processes and plunging the entire mass into formalin for 

 later removal of the hypophysis. As soon as possible the excess 

 dural sheath is removed and the infundibular stalk cut off close 

 to the main body of the gland. The organ is again placed in for- 

 malin a few moments to moisten the outer surface which becomes 

 somewhat dry as a result of the handling. After blotting off 

 excess formalin the organ is weighed and then fixed three or four 

 days longer in fresh formalin. Without washing in water, the 

 tissue is dehydrated as usual, cleared in xylol and embedded in 

 hard paraffin (6o° C), reducing the duration in the paraffin both 

 to four or five hours by changing the paraffin at least three times. 



The organ is cut horizontally, i.e., through its greatest diam- 

 eter, and not sagittally as in the prevailing method. If one is to 

 depend upon a limited number of sections for an estimate of the 

 condition of the gland, the view obtained in the horizontal plane 

 is by far the best. Mid-sagittal sections are particularly atypical 

 of pars anterior for this region is frequently very poor in eosino- 

 philes. Sections are cut 10 m till one fourth through the block 

 when an even number (about 10) of 5 m sections are cut for cy to- 

 logical work and differential cell counting. Cutting at 10 m is 

 resumed until the middle of the block is reached and again till 

 three-fourths through when similarly a few 5-/1 sections are ob- 

 tained. These division points may be determined near enough 

 by marking the end of the paraffin block after it is trimmed for 

 sectioning. 



The whole series is marked off into groups of twenty sections 

 (two 5-M sections counting as one) and from the middle of each 

 group a io-m section is taken. These (usually 30 to 40 in number) 

 can be mounted on three or four slides and stained with Mal- 

 lory's connective tissue stain (acid fuchsin-aniline blue-orange G) 

 as regularly done in staining connective tissue. Another similar 

 set is taken from points midway between the other series and 

 stained with hematoxylin and eosin in order to have two series 



