Handbook of bacteriology for nurses / [Harry Wardwell Carey].

  • Carey, Harry Wardwell, 1875-1935.
Date:
1930
Catalogue details

Licence: In copyright

Credit: Handbook of bacteriology for nurses / [Harry Wardwell Carey]. Source: Wellcome Collection.

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    or in cubes, sarcinse. They are commonly arranged in long strings or chains termed streptococci, or in masses, often likened to bunches of grapes, staphy- lococci. The bacilli are rod-shaped, sometimes slightly curved, and vary greatly in length, from M.000 to %5ooo of an inch. They are slender or thick. Some have rounded ends, some are square at the end. A bacillus usually is of uniform width but a few are quite irregu- lar in this respect. They occasionally form in chains or rows. The spirilla are spiral or corkscrew-shaped, as the name implies. Some may be comma-shaped. They vary both in length and in the number of spirals. Of these three types the bacilli are by far the most numerous and the spirilla the least numerous. The types are not interchangeable; so it is not possible for a coccus to become a bacillus or a bacillus a spirillum. Questions in Review. 1. Define a bacterium. What is its structure? 2. How may bacteria be classified on the basis of their shape ? 3. Describe the arrangement of—staphylococci, streptococci, diplococci, tetracocci and sarcinae. 4. What class of bacteria exist in greatest number? What class in least number ?