112 GUIDE TO THE STUDY 



may first be put in half-strength solution and transferred after a 

 few hours to full strength. 



Glycerine Jelly. — Glycerine, 100 parts; distilled water, 120 

 parts; gelatine, 20 parts; carbolic acid, melted crystals, 2 parts. 

 Let the gelatine soak in water for a half hour and then dissolve 

 with gentle heat. Add about 5 cc. of egg albumen and heat 

 (not over 75°C.) for half an hour. Filter through moist hot 

 flannel and add the glycerine and carbolic acid. Warm for 10 to 

 15 minutes stirring continually. For mounting place a drop of 

 melted jelly in the center of a slide and transfer the object from 

 an aqueous solution or glycerine to the jelly and arrange it. 

 Lower a clean cover glass upon the object and gently press it 

 down. After the jelly has set, clean away any excess around 

 the cover and seal. 



Buxton's Medium. — Distilled water, 50 cc; glycerine, 20 cc, 

 gum arabic, 40 grams; chloral hydrate, 50 grams; cocain hydro- 

 chlor., 0.5 grams. Dissolve gum in water, add chloral hydrate 

 and cocain; when dissloved, add glycerine. Filter if necessary. 

 This is a very useful medium in which objects can be mounted 

 directly from water; alcohol specimens must be thoroughly washed 

 in water. Buxton, who used it particularly in studies of mites, 

 placed them in it on the slide in the living condition and found that 

 they died rapidly in an extended condition. 



Noyer's Lanoline Cement. — Langeron, who recommends this 

 cement highly, gives the following directions: Anhydrous 

 lanoline (mutton tallow), 20 grams, colophane (rosin), 80 grams. 

 The commercial lanoline is slowly heated in an evaporating 

 dish until the traces of water are driven off, and then the rosin 

 is added, the mixture being stirred continually until the fusion is 

 complete and perfectly homogeneous. Store in metal salve 

 boxes. The cement is applied by means of a heated wire bent at a 

 right angle some 22 mm. from the tip. Begin by putting a 

 drop of the cement at each corner of the cover and then rapidly 

 and smoothly applying to the edges. We have long used this 

 cement with perfect satisfaction. 



Apathy's Cement. — Equal parts of 60° paraffin and Canada 

 balsam are heated together in a porcelain evaporating dish 

 until the mass takes on a golden tint and no longer emits vapors 

 of turpentine. Apply with a warm wire or glass rod. 



Carbol-xylol. — This useful mixture will clear imperfectly 

 dehydrated objects directly from 95 per cent alcohol and thus 



