EXPLANATION OF PLATES. 



With the exception of figures 20, 27, 30, and 35, the drawings were made with the 

 aid of a camera lucida. For figures 3, 5 to 11, 15 to 17, 19, 21 to 26, 28, 29, 31 to 34, and 

 36 a no. 12 Bausch & Lomb compensating ocular and one-twelfth inch oil immersion 

 objective were used. For figures i, 2, 12, 14, and 18 a Bausch & Lomb i-inch occular 

 was employed with the same objective. The i-inch occular and a one-fifth inch objec- 

 tive were used in figures 4 and 13. All figures have been reduced to two-thirds the size 

 of the camera images. The tube length was 160 mm. and the camera arm 90 mm. 



The figures are numbered approximately in the order of development. Figures 2, 



3, 5, 6, 7, 8, 9, and 10 are made from the same slide, and figures 13, 14, 16, 17, 18, 26, 



and 28 are from the same fish. 



Plate XX. 



Fig. I. A bit of infected muscle from a smear of a sore on the side of a small Fundulus heterclilus in 

 the first stage of disintegration. Fixed in corrosive sublimate and acetic acid and stained with Mayer's 

 hsematein. The pale bands of the fiber are beginning to become granular at one end. Fibrin threads 

 have been spread over it in making the smear preparation. ( X860.) 



Fig. 2. A bit of degenerating muscle fiber. Numerous artifacts and a degenerate erythrocyte 

 nucleus occur in the sarcoplasm. The granular striae are degenerated sarcolymph. Note the sarco- 

 plasm is also becoming granular. (X860.) 



Fig. 3. From a smear of a bit of degenerating muscle in a sore on the side of Fuiidtilus majalis. 

 The integument more or less disintegrated, scales entirely absent. Fixed in absolute alcohol, ether, 

 and formaldehyde. Stained in methylene blue, orange G, and eosin. Sarcous elements have lost 

 their sharp rectangular form and are becoming granular. A characteristic muscle artifact is distributed 

 between the sarcostyles and some are just beginning to become amoeboid in form. (X2000.) 



Fig. 4. A characteristic appearance of a degenerating muscle fiber which may or may not be a later 

 stage than those represented in figures 2 and 3. Neither bacteria nor M)rxosporidia are necessarily 

 present in these spaces. Both have been encountered there. (X400.) 



Fig. 5. A fragment of degenerating muscle upon and into which erthrocytes and leucocytes have 

 entered. The cytoplasm of the latter is disintegrated and the nuclei are in an advanced stage of 

 degeneration. (X2ooo.) 



Fig. 6. A typical mass of degenerate nuclei containing unstained bodies which are probably zoogloea 

 containing the short bacillus. There are cords of this material in which the bacilli are faintly visible. 

 Such white areas are not merely transparent spaces but thick masses with stainable protoplasm above 

 or below. (X2000.) 



Fig. 7. Artifacts from decomposing muscle fibers. In fresh muscle these are common after 10 to 

 12 hours, appearing first between the sarcostyles. Older stages assume a more compact form. (See 

 figures 3 and 2.) The stain is a homogeneous pale blue. Maximum length 8.9/1. (X2000.) 



Fig. 8. The short bacillus. An isolated group near which are located cells containing white oval- 

 shaped bodies like those in figure 6. Note the variation in size and shape. That one near the " X" 

 sign measures 1. 5fi by 7. 4«; that near the "-[-" sign measures 1.8/1 by i.i/(. (X2000.) (See also fig. 10.) 



Fig. 9. Short bacillus older than figure 8. Nearly the maximum size. Note the taper toward 

 one end and the stainable granules. The latter are probably artifacts. Left-hand upper one measures 

 5.2/1 by 1.4/i. (X2000.) 



Fig. 10. A cluster of long bacilli which have caused the complete breakdo\vn of a tissue cell and 

 rest in situ. (X2000.) 



Fig. ir. Several of the long type of bacilli which are located just under the sarcolerama of a muscle 

 fiber that shows the first signs of degeneration. The small individual in the middle below has dimen- 

 sions as follows: Length, 4.8/1; thickness, 0.7/1. (X2000.) 



