CHROMOTROPE BLUE 2R 



67 



CLARK AND LUBS BUFFERS 



Chromotrope Blue 2R, see Chromotrope 2R. 



Chrysamine G (CI, 410) an acid dis-azo dye 

 of light fastness 5 of no value as a tissue 

 stain (Emig, p. 40). 



Chrysoidin Y (CI, 20)— brown salt R, dark 

 brown salt R — A basic mono-azo dye 

 suggested by Conn (p. 46) as a substi- 

 tute in some techniques for Bismark 

 brown. Used as stain for mitochondria 

 and Golgi apparatus viewed in polarized 

 light (Monne, L., Protoplasma, 1939, 

 32, 184-192). 



Chrysophenine (CI, 365), a direct dis-azo dye 

 of light fastness 4 to 5, for paraffin sec- 

 tions too light and fugitive a color 

 (Emig, p.39). 



Chylomicrons (lipomicrons). These tiny 

 fatty droplets are easily demonstrated by 

 dark field examination of blood of a person 

 or animal fed butter or cream. The 

 increase begins about 1 hr. there after 

 and reaches a maximum at 4 hrs. after 

 which the number of chylomicrons de- 

 clines. By contrast a carbohydrate meal 

 of rice and sugar or a protein meal of 

 whites of boiled eggs and salt does not 

 result in an increase. For details see 

 Gage, S. H. and Fish, P. H., Am. J. 

 Anat., 1924-25, 34, 1-86; also, Had- 

 jiolotf, A., Bull. d'Hist. Appl. 1938, 

 15, 81-98. 



Ciaccio, methods for lipoids. One of the 

 simplest is : Fix small pieces 2 days in : 

 5% potassium bichromate, 80 cc; for- 

 malin, 30 cc, acetic acid, 5 cc. 3% 

 potassium bichromate for 5-8 days. 

 Running water 24 hrs. Ascending alco- 

 hols, 24 hrs. Abs. alcohol 2 hrs., xylol, 

 1 hr., xylol -paraffin at 60 °C., 1 hr. 

 Paraffin 1-1 J hrs. Pass sections down 

 to 70% alcohol, stain ^1 hr. at 30 °C. 

 in: 80% alcohol, 95 cc, acetone 5 cc. 

 saturated at 50°C. with sudan III then 

 cooled and filtered. Rinse in 50% alco- 

 hol, wash in water, counterstain with 

 hemalum. Mount in syrup of Apathy 

 (or glycerin). Lipoids yellow orange. 

 Lison (p. 206) questions specificity for 

 lipoids and gives in addition, with useful 

 comments, several other methods of 

 Ciaccio. 



Cilia. The cjuickest method is to remove a 

 piece of fresh ciliated epithelium from 

 the respiratory nasal mucosa of an anes- 

 thetized or recently killed animal. Cut 

 up finely with scissors, tease out small 

 pieces with needles, mount in isotonic 

 salt solution and examine at low mag- 

 nification in the dark field. A simple 

 technique of demonstrating the move- 

 ment of cilia is to examine at a mag- 

 nification of about 80 diameters the 

 epithelium of the roof of a frog's mouth 

 by reflected light. The angle between 

 incident and reflected light should be 

 about 90°. A strong source of illumina- 

 tion is required with a water screen to 



remove the heat. A useful set up is 

 described and illustrated by Lucas (A. 

 M., Arch. Otolaryng., 1933, 18, 516-524). 

 Many excellent moving pictures have 

 been made of ciliary action of which 

 one by Dr. Arthur Proetz is recom- 

 mended for teaching purposes. 



When cilia are present they can be 

 seen in almost any proi)erly stained 

 section of well fixed material. A good 

 stiiin for cilia is iron hematoxylin with 

 suitable counterstain, after formalin- 

 Zenker fi.xation. Engelman (Lee's Vade 

 Mecum p. 509) found that ciliated cells 

 of Lamellibi-anchs could be well iso- 

 lated by maceration in 4% aq. potassium 

 bichromate and in 0.1% osmic acid. 

 This should be tried for mammalian 

 ciliated cells. Cilia and their basal 

 granules are often sharply blackened by 

 silver impregnation. See Cowdry's de- 

 scription of flagellated thyroid cells of 

 the dogfish (Cowdry, E. V., Anat. Rec, 

 1921, 22, 289-299). Centrosomes and 

 diplosomes are often revealed in ciliated 

 cells particularly in those undergoing 

 differentiation. See Centrosomes. Lit- 

 erature on ciliated epithelia is well 

 presented by Lucas in Cowdry's Special 

 Cytology, 1932, 409-474. See his illus- 

 trations. Application of technique of 

 microdissection to ciliated cells is de- 

 scribed by Worley, L. G., J. Cell. & 

 Comp., 1941, 18, 187-198. 



Cinephotomicrography. A convenient illus- 

 trated account of apparatus and meth- 

 ods is given bv Tattle, H. B., in Glas- 

 ser's Medical Physics, 183-194. See 

 Motion Pictures. 



Cinnamon Oil (Cassia oil) resembles clove 

 oil and is particularly recommended by 

 Lee (p. 70) for clearing. Two kinds are 

 given in Merck Index. The U.S.P.XI 

 variety contains 80-90% cinnamalde- 

 hyde . 



Citrate of sodium can be used as an antico- 

 agulant in the proportion of 18 cc. of 2% 

 aq. sodium citrate to 100 cc. of blood. 



Clarite X (Neville Co., Pittsburg) 60% in 

 toluol is suggested as substitute for 

 balsam owing to its neutral reaction, 

 lack of yellow color and quickness of 

 hardening. Clarite, also called Nevil- 

 lite V, is useful if added to paraffin when 

 one wishes to obtain thin sections when 

 it is not convenient to imbed in a very 

 high melting point paraffin. Wehrle, 

 W., Stain Techn., 1942, 17, 131-132 ad- 

 vises imbedding in a mixture of 90% 

 paraffin (m.p. 53°C.), 5% bleached bees- 

 wax and 5% clarite and the elimination 

 of electrical charge when ribbons are 

 cut by a spark-coil device described by 

 Blandau, R. J., Stain Techn., 1938, 13, 

 139-141. 



Clark and Lubs Buffers (Clark, W. M. The 

 Determination of Hydrogen Ions, Balti- 



