2390 Journal of Applied Microscopy 



CYTOLOGY, EMBRYOLOGY, 



AND 



MICROSCOPICAL METHODS. 



AGNES M. CLAYPOLE, Throop Polytechnic Institute. 



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



55 S. Marengo Avenue, Pasadena, Cal. 



Schoenemann, A. Farbung und Aufbewahr- The author encountered a need for 

 ung von Schittserien auf Papierunterlage. , ,, i • i i t i 



Zeitschr. f. wiss. Mikros. u. f. mikr. Tech. goo^ methods m embedding and sec- 

 19: 150-161, 1902. tioning large objects, to be kept after- 



wards. The author tried plans to see whether it would be possible to fasten 

 unstained microscopical celloidin or paraffin sections direct on a flexible suitable 

 stain-proof paper. The following process resulted from his efforts : 



Sections were desired of the nasal cavity of infants and the petrous bone of 

 adults. These were decalcified in 7 per cent, sulphuric acid, or saturate solution 

 of sulphurous acid. As long as the material remained in the acid it was hard, 

 but on removal to water the altered salts were dissolved. The objects were then 

 put in absolute alcohol for an hour or a day, according to the size, and trans- 

 ferred to a mixture of ether 2 parts, oil of cloves 1 part, then into Stepanous 

 collodion solution (celloidin chips 1.5 grm., clove oil 5 grms., ether 20 grms., 

 absolute alcohol 1 grm., added by drops). Small objects were left in this for a 

 couple of hours, larger ones for the same number of days. When infiltration is 

 complete the objects are oriented in paper boxes on a sheet of glass and em- 

 bedded, hardened for twenty-four hours in chloroform, then the paper is 

 removed and the objects again put into chloroform. If the wet method is 

 used chloroform is omitted and the blocks hardened in 80 per cent, alcohol, but 

 the author prefers the dry method, sticking the block on with thick collodion or 

 paraffin and using the knife at an angle of about 40°. Strips of tracing paper 

 which has been so treated with minerals as to be incapable of being stained 

 is used, one end being kept for notes, etc.; on the other are laid in order the 

 cut sections, which are later dried, flattened with filter paper ; there is no danger 

 of their sticking to the filter paper. These strips of paper, in their proper order, 

 are put into 80 per cent, alcohol, where the cedar oil is removed. It is impor- 

 tant that the strips should be piled on each other with a filter paper strip 

 between each, and a glass on the top to keep them flat during the hardening pro- 

 cess. In this liquid with several changes the sections may remain unhurt a long 

 time. For staining, the strips are put in water, and if cloudy spots appear it is 

 of no consequence. The sections are then stained (dilute hemalum, Gruebler's, 

 or dilute Grenacher's or Delafield's), for several hours, to make the nuclei clear. 

 When sufficiently stained, sections are put in tap-water and put in a solution of 

 eosin in 95 per cent, alcohol. From this they are put into carbolxylol (1-3), in 

 which all cloudiness and any excess of eosin disappears. Then a bath of xylol 

 is used to remove the carbolic acid, which would injure the staining properties 

 of the tissue. If they are to be studied wet the strips must now be put in cedar 

 oil, where they may be kept for some months without injury, and examined in 

 cedar oil on a slide covered with glass or mica. If they are to be dried, they are 

 coated with a varnish that will not become brittle and is free from alcohol and 

 ether. " Elaslinlack " (Griibler) is satisfactory; the paper strips lie in this mix- 

 ture for about twenty-four hours and are then fastened on a wooden frame. 

 They are dry in from twelve to twenty-four hours ; during the drying the strips 

 must be brushed over several times, to be sure the sections are well covered, 

 otherwise they may flake off. When after two to six days the strips are no 

 longer sticky, they are laid between filter papers in a cool place. a. m. c. 



