THE MYXOSPORIDIA, OR PSOROSPERMS OF FISHES. 265 
Myxosporidium.—The largest attaining 75 py (,'5/’ Lieberktihn), the 
smallest the size of a blood corpuscle; spherical or ellipsoidal, more 
rarely irregular, membraneless, containing irregularly scattered fat-like 
globules. 
Spore formation.—Many myxosporidia appear destitute of fat gran- 
ules, but show a large number of structureless gelatinous globules; 
other myxosporidia show partly the same globules, partly similar ones 
of the same size containing 4 capsules whose apices are approximated. 
Many globules show only faint indications of such capsules. Sometimes 
2 such globules occur inclosed within a common structureless mem- 
brane. Besides these, developed psorosperms occur, both individually 
ana in heaps, held together by a mucoid substance. 
Spore.—Sharp-contoured, subglobular, mucronate anteriorly; length 
ad max., 8 uw; capsules 4, converging anteriorly. 
Habitat.—Free in urinary bladder of Lota lota L. (ling). Found in 
about 20 per cent of the fishes examined. 
Remarks.—Lieberkiihn emphasizes the striking resemblance between 
this species and those described by Leydig from the gall-bladder of the 
Plagiostomes (Chloromyxum leydigit and C. incisum). He notes, how- 
ever, that C. mucronatum differs from Leydig’s forms in the absence of 
a membrane around the myxosporidium, and in the absence of the pan- 
sporoblastic vesicles (Leydig’s Tochterblase). From later researches it 
is easy to interpret Lieberkiihn’s results in harmony with those of Ley- 
dig, as the vesicle stage of the pansporoblast is merely a later stage of 
the gelatinous globules of the above description (see pp. 81, 286). 
SUBGEN. SPHAROSPORA Thélohan, 1892. 
_ Etymology not given. 
Bull. Soc. philomat. Paris, Iv, p. 175; Myxosoma et Mixosoma!, ibid., p.175; 
subgen. (including Myxosoma and Mixzosoma) of Chloromyxum, Gurley, 
1893, Bull. U. S. Fish Com. for 1891, x1, pp. 411-412, 418-419; Spherospora 
et Myxosoma, Braun, 1893, Centralbl. f. Bakt. u. Parasitenkde, xIv, p. 739; 
ib., Braun, Centralbl. f. Bakt. u. Parasitenkde, xv, p. 87. 
Definition.—Bicapsulate Chloromyxa; type Chloromyxum (S.) elegans. 
Species.—The study which, through the kindness of Dr. Ohlmacher, 
I was able to make of C. (S.) ohlmachert enabled me to recognize 2 
other species in the literature which should be referred to this sub- 
genus. The first is Balbiani’s spore of Acerina cernua, which I have 
named Mywxobolus perlatus. The median anterior and posterior mucro- 
nate projections and the median line shown in Balbiani’s figures, can be 
respectively interpreted only as the ends and the intervening portion 
of the ridge. In other words, the valve-junction plane is vertical. The 
appearances are identical with those shown by C. ohlmacheri. The 
second is Biitschli’s spore of the ovary of Lota lota. Though Biitschli’s 
figures represent it as bicapsulate it should be compared with C. mucro- 
natum. 
1Type Mvrosoma dujardini. 
