The handling of chromosomes / by C.D. Darlington and L.F. La Cour.

  • C. D. Darlington
Date:
[1960], ©1960
Catalogue details

Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: The handling of chromosomes / by C.D. Darlington and L.F. La Cour. Source: Wellcome Collection.

    184/282 (page 154)
    154 THE HANDLING OF CHROMOSOMES ScH. 3.—ACETIC-LACMOID SQUASH METHOD. Tissues: Root tips, embryo sacs, pollen grains. [A. Fix in acetic alcohol ia-24 hours.] For rapid counts in root tips, fixation can be reduced to 10 mins. or even omitted. B. Stain by placing tissues in a watch-glass containing a few drops of: 10 c.c. standard acetic-lacmoid, plus i c.c. N.HCl. C. Heat without boiling 2-3 times over a spirit flame. (Vary the amount of heating according to the hardness of the tissues.) Leave 10 mins. D. Tease out the tissues on the slide in a drop of fresh standard solution. E. Place filmed cover slip in position. Apply pressure under several thicknesses of blotting paper, allowing no sideways move¬ ment of the cover slip. F. Mount as in Sch. 2'. Note.—Lacmoid can be replaced with orcein if desired {cf. Tjio and Levan 1954). ScH. ЗА.—RAPID TUMOUR SQUASHES (Koller 1942). A. Fix small pieces in acetic alcohol, 10 mins.-24 hours. B. Transfer shreds of tissue. 10% acetic acid 5 mins., 45% 10 mins. C. Stain in acetic-lacmoid or -orcein at 40° C. for 15-30 mins. D. Macerate stained tissue in a drop of the stain on slide. E. Remove unmacerated fragments. F. Cover with filmed slip and press to spread cells. G. Seal, or make permanent as in Sch. 2.