304 KEPOET OF THE COMMISSIONER OF FISH AND FISHERIES. 



Plate 46. 



FigB. 1-3. Myxidinm Ueterlcuhvii. 



1. Epithelial infection of bladder from fresh and also from hsematoxylin-stained 



material (after Pfeiffer. X 1). 



la. To the left liealtliy, to the right slightly hypertrophied epithelia which have 

 lost their nuclei. At the right border, monstrously enlarged epithelia, or 

 rather myxosporidia, with fat and ha'Uiatoidin contents; nucleus obscure. 

 Below to the left an isolated epithelial cell with early infection, and the 

 disrupted epithelial nucleus. 



lb. Immigration of young myxosporidia into the red blood corpuscles of Lucius 

 htciiiii. Nucleus, where preserved, dark. In the upper row the middle cor- 

 puscle shows a multiple infection. Lower row showiui; not spore formation, 

 but fat globules, nuclei, and htematoidin crystals. In the lower right-hand 

 figure the myxosporidium has left the blood corpuscle and developed its 

 hyaline ectoplasm. 



2. Myxosporidia (after Balbiani. X 1). 



2a. Myxosporidium filled with fatty granules without pansporoblasts. 

 2b. Myxosporidium with well-developed spores. 

 2c, d. Very young myxosporidia. 



3. Pansporoblast containing 2 mature spores (after T.ieberkiihn. X f). 



Plate 47. 



Figs. 1-5. Myxidium lieherkiihiiii. 



1. Spore formation (after Biitschli. X 1). 

 la. Pansporoblast with nuclei. 



lb. Tlie pansporoblast has contracted its bulk somewhat, elongated to an oval, 



and oriented its nuclei preliminary to division. 

 Ic. The sexanucleate pansporoblast has divided into 2 spherical triuucleate 



sjioroblasts. 

 Id. The sporoblasts have elongated and oriented .^nemselves and their nuclei. 

 le,f. Showing the develo])ment of the capsules ii iejjendently of the vanishing 



terminal nuclei. In the center of the spore its nucleus (see p. 287). 



2. Developed spore (after Lieberkiihu. X f ). X 900. 



3. Mature spore (after Biitschli. X 1). Showing outline, bilateral symmetry, 



capsules, sporoplasm, and nucleus (see p. 287). 



4. The same (after Balbiani. x 1). 



ia,b. Most common form of spores with 1 capsule in each wing; b, with fila- 

 ments extruded. 

 4c. Rarer form of spore with 2 capsules in each Aving. 



5. Siiore with filaments extruded (after Biitschli. X 1). 



Fig. 6. Mi/xidium ? sp. 102. Showing spore with capsules separated ( ? in each wing.) 

 (After Leydig. X f). 



