The division and post-fission movements of bacilli when grown on solid media / by G.S. Graham-Smith.

  • Graham-Smith, G. S. (George Stuart), 1875-1950.
Date:
1910
Catalogue details

Licence: In copyright

Credit: The division and post-fission movements of bacilli when grown on solid media / by G.S. Graham-Smith. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    more accurately described as lateral outgrowths composed of spirally twisted threads, are thrust out into the medium. At other places the attempt at loop formation results in the chain becoming much twisted on itself, and gives rise to the appearance of knots on the chain. Finally the colony consists either of a single knot or a series of knot- like masses, surrounded by wavy outgrowths composed of spirally twisted chains of bacilli. Parallelism such as is seen in superficial colonies never occurs in deep colonies. In Plate IV (Figs. 1 to 10) a series of photographs (x about 80) are reproduced illustrating the formation of a deep colony from a single anthrax bacillus. In Fig. 1 a long wavy chain is seen, whose development from a single bacillus has been followed. Fig. 2 (15 minutes) shows an increase in length and a marked irregularity in the chain some little distance to the left of the centre. In Fig. 3 (45 minutes) the irregular area previously seen has become more distinct. In Fig. 4 (80 minutes) two small processes, just beginning to develop, can be made out one on each side of the irregular area and some distance from it. This figure also shows projecting processes one on each side of the irregular area. In Figs. 5 and 6 (117 and 135 minutes) the development of these processes may be followed. In Fig. 6 the irregular area now resembles a knot. Figs. 7, 8 and 9 (165, 210 and 285 minutes) illustrate further development. Fig. 10 (450 minutes) shows the fully developed colony. The irregular area first noticed has developed into a large knot, and several smaller knotted masses, produced in the same way, are seen along the length of the colony. Many irregular processes project laterally from the colony, some of which have developed knots in their length. At each end the colony terminates in a wavy thread. In Figs. 6 to 10 another colony can be followed developing above the original colony, and in Figs. 7 to 10 a third colony developing below it. Owing to their uneven disposition photographs of deep colonies have to be taken at such a low magnification that the details of the development of knots cannot be followed. While the photographs just described were being taken drawings were made at the same time on a larger scale. Diagram 2 reproduces a series of drawings showing the development of the irregular area from the condition seen in Plate IV, Fig. 2 to the condition seen in Plate IV, Fig. 5. In Diagram 2, Fig. 1 (15 minutes) the structure of the irregular area is clearly shown. It is caused by several definite loops in the course of the chain, at two of which (A and B) the chain is sharply