288 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 



disappearance of shell-contour, significant changes occur, involving capsules as well 

 as aporoplasm, the capsules behaving throughout as integral j>arts of the " proto- 

 plasmic contents." The sporopiasni, previouslj^ very transparent, bluish, rather 

 strongly refringent and destitute of granules, becomes paler, sharply contoured 

 granules rapidly appear in spots, and these very delicately contoured, round- 

 elongate or irregular [formerly sporoplasmic, now become myxoplasmic] masses grow 

 slowly or rapidly to small, strongly granulated plasmodes which already show some 

 yellowish or reddish-yellow pigmented spots. 



Gabriel has also the following strange statement as to the subsequent 

 course of development: 



Now it appears very peculiar that these 3 constantly present, morphologically 

 individualized, delimited, constituent parts [sporoplasm and 2 capsules] should, in 

 their further development, be restricted to a double course, viz, either fusing to a 

 single protoidasmic mass or remaining in the original state of separation; in the 

 latter case, falling apart by a rapidly progressing division, each into 2 (rarely more), 

 approximately equal, parts. 



Growth of myxosporidium (Pfeifier). — The young myxosporidium 

 [heretofore termed the sporoplasm], immediately after its exit from the 

 spore, j)enetrates into the interior of the red blood corpuscles and of 

 the cells of the bladder epithelium. The infection of the former may 

 be followed under the microscope. After 8 to 12 hours they shoAy 

 a noteworthy alteration, having become pale and, instead of 1 nucleus, 

 containing 2, 3, or more nuclei. One of these nuclei is jagged, or 

 wrinkled; the other (or others) is somewhat smaller, smooth, round, 

 shining, and occupies (with reference to the jagged nucleus) a variable 

 position. Htematoxylin stains the jagged nucleus dark, the smooth one 

 bright. With the increasing growth of the smooth nucleus the jagged 

 one rapidly falls to pieces, and its remnants become j)ressed against the 

 cell wall. Methylen blue and phloxin red stain the disrupted jagged 

 nucleus black-blue, the other a uniform red. From these observations 

 and the analogy of Lacerta and Testudo blood, the jagged nucleus is 

 to be regarded as the cell nucleus, and the smooth nuclei as intruded 

 myxosporidian germs. Here, too, the multiple infection {Mehrlingsin- 

 feJction) Is repeated. 



Microscopic technique. — Removed from their normal habitat, the 

 myxosporidia rarely remain intact more than 24 hours, and then only 

 in "indifferent" liquids, preferably (besides iodized serum) a 1-5 per 

 cent sodium carbonate solution or a 0-5 per cent sodium chloride solution 

 (Gabriel). Phloxin red and methylen blue stain the ectoplasm a 

 sharply defined red, the entoplasm inclusions blue. This striking result 

 causes the myxosi^oridium to resemble a true rhizopod (Pfeiifer). 



Habitat and frequency. — Urinary bladder of Lucius lucius (pike). 

 Most frequent and most highly developed in late summer and autumn; 

 rare in winter; thence increasing in frequency. Size and age of host 

 exert no influence (Gabriel). Free-floating in urine or attached (by 

 pronged end). Biitschli observed young examples with one end partly 

 surrounding an epithelial cell which had been torn away, thus present- 

 ing a Gregariue-like mode of attachment. Observed by Lieberkiihn 



