Page:Bergey's manual of determinative bacteriology.djvu/61



I. Cells usually combined into aggregates.


 * A. Cells grouped as regular sarcina packets.


 * B. Cells not in sarcina packets.


 * 1. Aggregates in the form of a flat sheet.


 * a. Cells in regular arrangement, with tetrads as the common structural unit.


 * aa. Cells in irregular aggregates.


 * 2. Aggregates in the form of three-dimensional masses.


 * a. Cells distinctly rod-shaped and arranged in a net-like structure.


 * aa. Cells not so arranged.


 * b. Cells in a common capsule, individuals rather scattered and loosely grouped.


 * bb. Cells in rather dense clumps.


 * c. Aggregates embedded in conspicuous common slime capsule.


 * d. Aggregates small, compact, often several of them enclosed together in a common capsule.


 * dd. Aggregates large and solid, later break up into small clusters.


 * cc. Common capsule lacking or very transient.


 * d. Aggregates as a whole exhibit amoeboid movements.


 * dd. Aggregates devoid of amoeboid movements.

II. Cells usually occurring singly.


 * A. Cells clearly spiral-shaped.


 * B. Cells not spiral-shaped.


 * 1. Cells irregular, often swollen, distorted, or composed of long, crooked and bent rods to filaments.


 * 2. Cells regular, spherical to short rods or bean-shaped.


 * a. Cells spherical, as a rule non-motile, and each one surrounded by a rather wide capsule.


 * aa. Cells ellipsoidal, ovoid, short rods or vibrios, actively motile.

(Zur Morphologie und Physiologie der Bacterien, I. Schwefelbacterien, Leipzig, 1888, 104.)

Thi.o.sar.ci′na. Gr. noun thium sulfur; M.L. fem. n. Sarcina a genus of bacteria; M.L. fem. n. Thiosarcina sulfur Sarcina.

Individual cells spherical, forming regular cubical packets of sarcina-shape, resulting from consecutive division in three perpendicular planes. Packets commonly containing 8 to 64 cells. Infrequently motile. Non-spore-forming. Contain bacteriochlorophyll and