Mar. 12, 1917 
Spore-Forming Bacteria of the Apiary 
403 
greater difficulty of getting good stained preparations of spores measure¬ 
ments were taken from the best preparations obtainable, regardless of 
the age. 
(1 b ) Spores— At first it was thought that B . mesentericus with small 
spores was quite sharply marked off from B . vulgatus with relatively 
much larger spores. In general, strains of B. mesentericus have much 
smaller spores than those of 13 . vulgatus; yet there are strains of B. mes¬ 
entericus that have comparatively large spores and strains of B . vulgatus 
which have comparatively small spores. Spores probably do not vary 
as much as do the vegetative forms. 
flagella 
In staining for flagella the technic employed by Williams, as presented 
in Mallory and Wright (io), * 1 gave the best results. 
Motility. —No trouble is experienced in observing motility in any of 
the strains studied. Besides the ordinary hanging drop, the scheme of 
cutting small blocks from cultures growing on thin agar in petri dishes, 
and inverting just as in a hanging drop over a concavity in a slide, is 
very instructive in studying form and movement. The germination of 
spores may also be studied by this method. The small blocks can easily 
be made to adhere to the surface of the cover slip by applying a small 
amount of sterile bouillon. 
Staining. —Basic carbol-fuchsin is quite satisfactory for staining and 
is used almost exclusively. In staining by Gram’s method, young 24- 
hour-old agar cultures are used and the stain is prepared fresh each time 
as follows: 5 per cent carbolic-acid solution, 10 parts; saturated alcoholic 
solution of gentian-violet, 1 part; allow the stain to remain on the thin 
smear for 5 minutes; without rinsing put in a watch glass and cover with 
i Williams’ method for staining flagella: 
1. Flood the cover glass with a mordant consisting of: 
Alumnol i% solution 5 c. c. 
Osmic acid 2% solution 5 c. c. 
Tannin 20% solution 5 c. c. 
Shake the mixture and add three drops of glacial acetic acid and shake again. 
2. Apply the mordant less than one minute without heating. Wash thoroughly in water. 
3. Cover the preparation during about one minute with a 1% solution of Ag NO3 to which sufficient 
ammonium hydroxide has been added to keep the silver in solution, 
4. Wash in water. 
5. Wash with 0.6% solution of sodium chloride. 
6. Flood the preparation with a'30% solution of ammonium hydroxide and immediately wash in 
water. 
7. Apply a few drops of Ortol photographic developer. The directions for making up this devel¬ 
oper come with the Ortol. 
8. Wash in water. 
9. Cover with a 1% solution of gold chlorid during a few seconds. 
10. Wash in water and apply Ortol developer for a few seconds. 
xi. Wash in water and cover with a z% solution of mercuric chlorid for a few seconds. 
12. Wash in water. 
13. Apply Ortol developer for a few seconds. 
14. Wash in water and repeat the application of chlorid of gold, the washing and the application 
of the developer two or more times. 
One can substitute other developers for the Ortol with apparently as good success. A trial of the method 
will serve to convince that it is not so long or complicated as a perusal of the directions would indicate. 
