Temporary Slides Research Articles

Chromosome Number in the Blue Fox (Alopex lagopus (L.))

THE materials examined consisted of testes from five farm-bred blue foxes (Alopex lagopus (L.)) which were killed by electrocution during the breeding season. The testes were immediately removed, teased in distilled water where they remained for about 10 min. and then the pieces were put in either aceto-orcein or 50 per cent acetic acid. From the aceto-orcein coloured preparations, temporary slides were made by the usual squash methods. The preparations fixed in 50 per cent acetic acid were squashed in the same manner and coloured by the Feulgen method1.

Chromosome number in the silver fox (Vulpes fulvus Desm.).

Two male silver foxes were killed by electrocution on February 1. The testes were teased in distilled water, where they remained for 10 min., and then the pieces were put into aceto-orcein and temporary slides were made by the usual squash methods.

Chromosome number in the ferret (Putorius furo).

THE testes of two male ferrets were teased in distilled water, where they remained for about 10 min., and then the pieces were put into aceto-orcein and temporary slides were made by the usual squash method.

An improved sealing wax for temporary smear preparations.

A mixture of polyethylene glycol 40002 and gum mastic as an improvement over the classic paraffin-mastic seal for temporary slides offers the following advantages: no stratification of components; delayed solidification permitting effective application of weights for flattening cells; solubility in 3:1 ethanol-acetic acid, thereby eliminating scraping for removal and so reducing the number of broken cover slips and paraffin artifacts. Hardness may be varied by using other grades of polyethylene glycol. Gum mastic is purified by treatment with acetone and hot water, after which it is mixed with molten polyethylene glycol. The author calls the product “Glycomastic”.

The Acetocarmine Smear Technic

The acetocannine smear technic is described primarily for beginners. An effort was made to bring together into one paper the work-a-day details to be followed in collecting specimens and making preparations of plant chromosomes at prophase, of condensed chromosomes at meiosis and mitosis (including mitosis in microspores), and of coiled chromonemata. A schedule for converting temporary slides into permanent mounts is given, and a technic for making smears of the chromosomes in the salivary glands of Drosophila is described.