228 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 



free) of Barbus barhufi L. (barbel) from the Rhine, Mosel, and Saar, 

 the barbels of the Elbe and Weser territory being free from them 

 (Pfeiflfer). Also once in heart cavity (Ludwig). In barbels from the 

 Marne, probably also from the Aisne and Seine (Railliet). Balbiaui 

 failed to find " adult psorosperms" in the viscera in Megnin's material 

 (Megnin). 



Liver, kidney, spleen, connective tissue of various organs; found in 

 ovary by Balbiani.^ In one case tlie myxosporidia and sjjores were 

 lodged in a sort of cavity in the connective tissue of the intestinal wall 

 10 cm. from the anus. They produced a very conspicuous thickening, 

 almost completely obliterating the lumen, 



Patholo(]\j. — Tumors:'^ A badly infected barbel showed about 40 

 tumors; fully 10 per cent of all the muscular fibers were filled with 

 spores. This condition must have resulted from auto-infection. The 

 tumors may soften to an irregular stinking abscess containing spores, 

 wandering cells, and the large bacilli (Pfeitfer ; see below under Ulcers)' 



Tumors, usually 10 to 15, ranging in size from a nut to a hen's egg, 

 with a very resistant wall 1 to 1-5 mm. thick; hemispherical or slightly 

 elongate; sometimes uniting into i)atches 17 to 20 mm. long by 7 or 8 

 mm. broad in fishes of 2*5 kilos (about 5 pounds) weight. Scales over 

 tumor raised, easily detachable, finally falling oif. 2S"ot all tumors open, 

 some fishes djiug before the ulcer stage. 



Some fishes die without external tumors, these being found located 

 in the viscera (Meuse; Railliet), Uusually of walnut size; sometimes, 

 however, 50 mm. long and 20 mm. thick, single or multiple, usually on 

 belly or sides; filled with a yellow or caseous purulent mass (Mosel, 

 Saar; fide Ludwig). 



^Fide Th(>lohan ( Annal. de Microgr., 1890, ii, p. 200 ; Compt. Rend, hobdom. Soc. Biol. 

 Paris, 1893, V, p. 268) who refers to Bnlhhiu'fH Lei^ons sur ler Sjyorozodircs. The only- 

 page of the last work to which the reference could apply is p. 147, and as M. Tholo- 

 han says (letter to author, 1803), Balbiaui is there not at all explicit. 



2 The following notes of four cases are from Lud wig. The ti.sh were { akeu al i ve from 

 the Mosel above Trier, died en route, and were examined the next day: 



1. ^ 30 cm. long; on left side .just above veuti-al fin a tumor 50 mm. long, 40 nun, 

 broad, and 30 mm. thick, extending above lateral lino; skin and omentum in neigh- 

 borhood of tumor normal. 



2. $ 47 cm. long; two tumors: (rt) on right side above ventral fin, under trunk 

 muscles (which latter were, around the tumor, reddened), 45 mm. long, 35 mm. broad, 

 and 15 mm. thick; covered by normal skin. Tumor so extended into body cavity as 

 to have driven the omentum heniia-like before it. {h) On left side in front of 

 pelvic bone, length 50 mm., breadth 15 mm.; already oiicned; orifice 10 mm. in 

 diameter with an irregular strongly reddened border, surrounded by reddened skin. 

 Cavity of ulcer filled wi>h l»loody mucus, which, apart from the admixture ofblood, 

 agreed with the tumor contents. 



3. $ 44 cm. long; on left side at level of lateral line, between ventral and anal 

 fins, a tumor 25 mm. long, 12 mm. broad, and 12 mm. thick; heart cavity filled with 

 same substance as tumor conteuts. 



4. (? 30 cm. long; in front of left ventral fin a tumor 35 mm. long, 25 mm. broad, 

 and 25 mm. thick, projecting but little externally, but greatly into abdominal cavity. 



