216 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 
lishes the conclusion that his reference to Gobio fluviatilis was due 
to an erroneous correlation between Lieberktihn’s text and Lieber- 
kiihn’s figures. Finally, Biitschli’s fig. iSa appears to be the transverse 
view of 18d. 
Concerning the relation between this form and MV. sp. 45, M. Thélo- 
han (letter to author, 1893) says: 
It is impossible to say whether this figure should be approximated to my Myxobolus 
of the bream. 
No description. 
Habitat—Branchie of Abramis brama 1. (bream). 
45. Myxobolus sp. incert. 
Myxobolus of bream, Thélohan, 1892, Bull. Soc. philomat. Paris, rv, p. 178. 
Cyst and myxosporidium not mentioned. 
Spore.—Length, 8 3 breadth, 6 to 7 py. 
Habitat.—Branchie of Abramis brama (bream). 
Remarks.—Differs from M. miillert only in the smaller size of the 
spores. See also remarks on the preceding species. 
46. Myxobolus miilleri Biitschli, 1882. Pls. 16, 17. 
(Myxosporidian spores of Squalius cephalus, of Barbus fluviatilis, and of other 
fresh-water Cyprinoids, Biitschli, 1881, Ztschr. f. wiss. Zool., Xxxv, p. 
630, footnote, pp. 630-8, 646-8, pl. 31, figs. 1-24.) 
Myxobolus miilleri, Bronn’s Thier-Reich, 1, pp. 595-7, pl. 38, figs. 6-10; ib. Lan- 
kester, 1885, Encycl. Britan., 9 ed., x1x, p. 855, fig. xv, 40, 415 1., 
Leunis, 1886, Synopsis d. Thierkde, 11, pp. 1157-8, figs. 1118-9; ib., Thélo- 
han, 1892, Bull. Soc. philomat. Paris, 1v, pp. 166, 167, 178; ib., Gurley, 
1893, Bull. U. S. Fish. Com. for 1891, x1, p. 414; 1b., Braun, 1893, Centralbl. 
f. Bakt. u. Parasitenkde, xiv, p. 739; ib., Braun, 1894, Centralbl. f. Bakt. 
u. Parasitenkde, Xv, p. 87. 
Synonymy.—Biitschli (1881) says the Myxosporidia investigated by — 
him came principally from the Cyprinoids, but that he could not give the 
species of host exactly, as he investigated large numbers of excised 
branchize. In part, however, these latter were derived from Squalius 
cephalus and from Barbus fluviatilis. He further states that he was 
unable to recognize any specific distinctions between the spores of the 
series he examined. Biitschl’s type figures of 1882 are copies of his 
figures of 1881. Parenthetically, also Lankester’s and Leunis’s are 
copies of these. Of those who have studied the pathogenic muscle- 
form of Barbus barbus (=fluviatilis), all admit its close similarity to, and 
some assert its identity with, M/. miilleri (see p. 225). Further, Pfeiffer 
states that in the Rhine basin, in which the epidemic produced by the 
muscle-form is very extensive, the branchivw are free from Myrospori- 
dia, & nonassociation that would seem to favor the idea of specific dis- 
tinetness. So far, then, no direct comparison has been made between _ 
the spores inhabiting the branchi of B. barbus and those inhabiting 
the muscles of the same fish. In the meantime it is probable that 
Leuciscus (squalius) cephalus L. should be regarded as, so to speak, the 
type host of M. miilleri, 
\ 
Be 
i 
“Sle ore eee eae 
