270 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 



largely distended and the kidneys were twice the normal size. ( )vai ios 

 modoiTitely developed, but not sufficiently to account for the abnormal 

 distension. Besides the Myxosporidia, the kidneys showed an extensive 

 invasion of bacteria. 



Effects. — There can, Ohlmacher says, be scarcely any doubt that the 

 Miixospoyidia were tlu; direct factors in the i)atliologic changes. Their 

 number was very great, the tubules of botli kidneys being tilled. The 

 mere mechanical elfect must have been obstruction of secretion and as 

 a remote result ascites and general o'denia. Undoubtedly the presence 

 of large numbers of bacteria (to be regarded as a secondary infection) 

 was a ])otent factor in hastening death. 



Subsequent (comparisons with sections of the kidneys of other toads 

 show the tubules in the first toad to have been dilated and their lining 

 cells to have been tlattened and less rich in i^rotoplasmic material than 

 normal. The kidneys of the 3 comparatively slightly infected toads 

 collected in July, 1803, showed no macroscopic lesions. IMicroscopically 

 no bacteria could be found. The absence of the bacteria, Br. Ohlmacher 

 thinks, probably had as much weight in determining the comparative 

 innocuity as the smallnessof the number of Jfi/xosjyoridia (letter, 1803). 



Through the kindness of Dr. Ohlmacher I have been enabled to 

 examine his specimens, and can add the following: 



Orienfatlon of the spore. — The capsules are 2. in I group, anterior; 

 valve-junction plane, vertical; shorter axis of spore, anteroposterior; 

 longer^axis, transverse. Sporoplasm showing no evidence of a vac- 

 uole, even in iodine-stained sectioTis. Beyond a slight median notch 

 in its posterior border (produced, I believe, by a slight inward, as well 

 as outward, projection of the ridge), I was not able to find any evidence 

 of sporoplasm-segmentation, and am therefore compelled to regard this 

 as an optical illusion, produced by the overlying ridge and reinforced by 

 the posterior median notch. 



This orientation necessitates the reference of this species to Chloro- 

 myxum [SpJicvrospoi-a). From C. (S.) eleguns it is distinguished by its 

 transversely elliptic outline and its dimensions. The fact of its iden- 

 tical organal distribution (renal tubules) should also be noted. 



Finally, Dr. J. B. Wliinery has recently published the results of a 

 careful detailed restudy of this species. He gives the following table, 

 showing the equivalence of Ohlmacher's nomenclature with that 1 

 have adopted: 



