and Laboratory Methods. 2017 



CYTOLOGY, EMBRYOLOGY, 



AND 



MICROSCOPICAL METHODS. 



AGNES M. CLAYPOLE, Throop Polytechnic Institute. 



Separates of Papers and Books on Animal Biology should be sent for Review to Agnes M. Claypole, 



55 S. Marengo Avenue, Pasadena, Cal. 



Voa Wendt. Georg. Eine Methode der Herstel- The author uses the following method 

 lung mikroskopischer Praparate, welche fiir as giving the best results : 1. Fixation 

 mikrophotographischeZweckegeeignetsind. ^^^ hardening. Material is cut in 



3 mm. blocks, fixed in cold 3 per cent, nitric acid for 12-20 hours ; nitric acid, 

 alcohol and picric acid are also suitable. The block is carried direct into 90 per 

 cent, alcohol for at least twenty-four hours. 2. Preparation for the first mor- 

 dant. Blocks are put into alcohol (75 per cent.) 10 pts., ammonia 1 pt., for 

 6-10 hours at a temperature of 15°C., and then again into 90 per cent, alcohol 

 for twenty-four hours. Then the tissue goes into alcohol (75 per cent.) 12 pts., 

 HCl. 1 pt., for 4-6 hours. After this it again goes into 90 per cent, alcohol for 

 twenty-four hours. 3. Mordant (A) 5 per cent, ammonium-wolframate or am- 

 monium molybdate solution. The so-called mordant is used for twenty-four 

 hours, first at a temperature of 17 °-20° C, andfor thelastfewhours, 12°-15°C.; 

 washing out in cold water and passing into 90 per cent, alcohol follows. 

 4. Imbedding. The usual paraffin method. 5. Cutting and fastening to slide. 

 Sections must not be too thick ; they are spread over warm alcohol, not water, 

 and fastened to slide or cover with Mayer's glycerine — albumin. Paraffin is re- 

 moved by xylol and slides carried as rapidly as possible to cold water. 6. Mor- 

 dant B. The water is drained off and a 2 per cent, iron-alum solution dropped 

 on to cover the sections. The slides are put for 2-7 minutes at a temperature 

 of 55° C, the thicker the sections the longer the time. Wash in cold water. 



7. Stain. A saturate solution of hematoxyUn in alcohol is dropped into distilled 

 water till the mixture has a moderately bright brown-gold color. This must 

 stand a long time before using. This is dropped on the slide in the same way 

 as the iron-alum solution, and allowed to act for ten minutes at 55° C. 



8. Differentiation. These are differentiated in cold iron-alum till the desired tone 

 is obtained. 9. Mounting. Washing in water and carrying to balsam by the 

 usual method. a- m. c. 



Previous work by this author has shown 

 Floresco, N. Correlation of Coloring in ^.j^^^ ^ g^ail with a dark shell has a 

 Liver, Skin and Hairs. Comptes Rendus, , i i i- i 



133:828-830,1901. dark mantle and dark liver; that a 



snail with a yellow-greyish shell has an 

 almost transparent mantle and yellowish liver. There is more iron in the livers 

 and mantles of snails with dark shells than of those with light shells. These 

 observations have been extended to dogs and cats, with the result that the liver 

 and skin of animals with dark hair contain almost twice as much iron and pig- 

 ment as those with light hair. , a. m. c. 



