304 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 
PLATE 46, 
Figs. 1-3. Myxidiwm lieberkiihnit. 
1. Epithelial infection of bladder from fresh and also from hematoxylin-stained 
material (after Pfeiffer. x 1). — 
la. Vo theleft healthy, to the right slightly hypertrophied epithelia which have 
lost their nuclei. At the right border, monstrously enlarged epithelia, or 
rather myxosporidia, with fat and hematoidin contents; nucleus obscure. 
Below to the left an isolated epithelial cell with early infection, and the 
disrupted epithelial nucleus. 
1b. Immigration of young myxosporidia into the red blood corpuscles of Lucius 
lucius. Nucleus, where preserved, dark. In the upper row the middle cor- 
puscle shows a multiple infection, Lower row showing not spore formation, 
but fat globules, nuclei, and hematoidin 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 Lieberkiihn. X $). 
PLATE 47. 
Figs. 1-5. Myxidium lieherkiihnii. 
1. Spore formation (after Biitschli. x 1). 
1a. Pansporoblast with nuclei. 
1b. The pansporoblast has contracted its bulk somewhat, elongated to an oval, 
and oriented its nuclei preliminary to division. 
1e. The sexanucleate pansporoblast has divided into 2 spherical trinucleate 
sporoblasts. 
1d. The sporoblasts have elongated and oriented themselves and their nuclei. 
le, f. Showing the development of the capsules independently of the vanishing 
terminal nuclei. In the center of the spore.its nucleus (see p. 287). 
2. Developed spore (after Lieberkiihn. xX #). x 900. 
3. Mature spore (after Biitschli. x1). Showing outline, bilateral symmetry, 
capsules, sporoplasm, and nucleus (see p. 287). 
4, The same (after Balbiani. xX 1). 
4a, b. Most common form of spores with 1 capsule in each wing; }, with fila- 
ments extruded. 
4c, Rarer form of spore with 2 capsules in each wing. 
5. Spore with filaments extruded (after Biitschli. X 1). 
Fig. 6. Mywxidium ? sp. 102. Showing spore with capsules separated (? in each wing.) 
(After Leydig. xX #). 
