320 
Ward . — Some Thames Bacteria . 
EXPLANATION OF FIGURES IN PLATES 
XX AND XXL 
Illustrating Professor Marshall Ward’s paper on Thames Bacteria. 
PLATE XX. 
I. Short Colourless Bacterium. 
Fig. i. Rodlets and cocci a actively growing on gelatine at ordinary tempera- 
ture ; b on gelatine at 20° C. ; c form from an old Agar-culture. 
Fig. 2. Gelatine plate-colonies at 20° C. a on the third day, b on the sixth 
day after making plates. 
Fig. 3. Culture from single rodlet. At 3 p.m. a rodlet (one of two) = 2 x 1 ft 
was fixed in gelatine at 20° C. a , at 10 p.m. this had divided b , and at n a.m. 
next morning it had formed the colony c: see p. 288. 
Fig. 4. Stab-gelatine, one month at 20° C. 
Fig. 5. Streak-gelatine, one week at 20° C. 
Fig. 6. Agar-culture, four days at 20° C. The layer in a consists of coalescent 
colonies shown slightly magnified in b. 
I 
II. Capsuled Coccus or Bacterium. 
Fig. 1. Plate-colonie^ at ordinary temperatures, a week old. a an emerged 
colony under ^ showing the characteristic streakings ; b a submerged colony 
natural size, and c the same under i showing the gland-like appearance; d a 
portion of a under E/4, showing the embedded zoogloea-masses. 
Fig. 2. Three submerged colonies, two days at 20° C. 
Fig. 3. A piece of Agar-culture, showing embedded zoogloeas : a under ^ ; 
b under X V imm. in water ; and c the same stained with methylene blue, showing 
the ‘capsule’ round the masses embedded in gelatinous matrix. The capsuled 
masses average 4-6 /x to larger and smaller : the organisms, 2xi/xtoixi^x. 
Fig. 4. Stained specimen after passage through animal ; preparation from 
plastic lymph ^ imm. Capsules hardly visible ; cocci 1 x 0-75 to 1 x 0.9 /x. 
Fig. 5. Similar from peritoneal fluid: the ‘capsules ’ visible. Cocci about 0-75 
to I-OJU. 
Fig. 6. Similar preparation from Agar-culture stained by Gram’s method. 
‘ Capsuled’ masses 6-10 ; rodlets 1 xo>6 to cocci about o*6 to 0-75 /x. 
Fig. 7. Colonies after one year’s rest, seven days’ plate at 18-20° C. Nat. size. 
Fig. 8. A ten days’ stab-culture showing commencement of the liquefaction. 
Fig. 9. A nine days’ streak-gelatine-culture. 
Fig. 10. An Agar-culture after revival. Five days at 35° C. 
