206 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 
Fam. MYXOBOLID Gurley, 1893. 
(Myxosporidiee! Perugia, 1891, Boll. Scientif., Pavia, x11, p. 28; Myxobo- 
lées Thélohan, 1892, Bull. Soc. philomat. Paris, Iv, pp. 178, 176.) 
Myxobolida, Bull. U. S. Fish Com. for 1891, x1, p. 413; Myobolea [Thél.] 
Braun, 1893, Centralbl. f. Bakt. u. Parasitenkde, XIv, p. 739; ib., Braun, 
1894, Centralbl. f. Bakt. u. Parasitenkde, xv, p. 86. 
Definition.—Phenocystes, whose spores are destitute of antero-pos- 
terior, but possess bilateral, symmetry;”? capsules 2, in 1 group at the 
anterior end; a bivalve shell, the plane of junetion of whose valves is 
parallel to the longitudinal plane; an iodinophile vacuole; type (and 
only) genus Myxobolus. 
IV. MYXOBOLUS Biitschli, 1882. 
Etymology not given. 
Bronn’s Thier-Reich, 1, pl. 38, figs. 6-10, and of subsequent authors; ib., Lank- 
ester, 1885, Encycl. Britan., 9 ed., xrx, p. 855; i0., Thélohan, 1890, Annal. 
de Microgr., 11, p. 213; Myxosporidium® Perugia, 1891, Boll. Scientif., Pavia, 
XII, p. 23; ib., Weltner, 1892, Sitzgsber. Gesellsch. Naturf. Freunde 
Berlin, p. 34; Myxosporidium, ibid., p. 35; Myxobolus et Henneguya*t Thélo- 
han, 1892, Bull. Soc. philomat. Paris, Iv, pp. 176, 177; Myxobolus, Perrier, 
1893, Traité de Zool., p. 460; ib., Gurley, 1893, Bull. U. 8S. Fish Com. for 
1891, x1, pp. 411-13; ib. peas 1894, Centralbl. f. Bakt. u. Parasitenkde, 
XV, p. 86. 
Definition.—Characters, those of the aril. 
Henneguyais separated from Myxobolus by only 2 characters, viz, (1st) 
capsules constantly 2, and (2d) the presence of atail. Inasmuch, how- 
ever, as all the numerous typical Myxobolus species have 2 capsules, and 
only 2 species are known to deviate in this respect in the direction of 
capsule-reduction, the typical number of capsules in Myxobolus is 2; so 
that the 2 differential characters in reality reduce to the single one of 
the presence of a tail. This in itself is not sufficient to warrant a 
generic separation, especially in view of the entire accord between the 
tailed and uti tiled forms in regard to symmetry, similar position of the 
valves, exactly similar vacuole, nuclei, etc. Besides, it may be noted 
that it has been several times asserted that tailed and untailed forms 
occur in the same cyst. Thus Miiller,’ Lieberkiihn,® and Biitschli’ 
1 Myxosporidium Perugia (synonym for Myzxobolus Biitschli?) proposed as type 
of Fam. Myxosporidiew Perugia, by the author in Bull. U. 8. Fish Com. for 1891, 
X1, p. 418. 
2Except species which have suffered reduction of characters (Myxobolus unicapsu- 
latus, M. piviformis, M. inequalis). Perhaps M. strongylurus should be added. 
3 Myxosporidium merlucit proposed by the author (Bull. U. S. Fish Cem. for 1891 
(1893), x1, p. 413) as the type species. The name Myxosporidium, having been pro- 
posed as a new name for a genus formed by the fusion of several good genera each 
of which already possessed a name in good standing, must be suppressed. 
4 Henneguya psorospermica proposed as the generic type by the author (Bull. U. 
8. Fish Com. for 1891 (1893), x1, p. 413). 
5 See Myxobolus sp. 61, p. 240. 
6 Miiller’s Archiy.,1854, p. 6; Mém. Cour. et Mém. Sav. Etrang. Acad. Roy. Belg., 
1855, XX vg, p. 37. 
7Bronn’s Thier-Reich, 1882, 1, p. 597. This is probably only an opinion as to the 
consensus, and not an independent one. 
=) a? 
