188 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 
‘ 
seen in way of further division), the cell-nucleus being as yet unaltered. 
With continually progressing division, both of the myxosporidium and 
the cell nuclei, and with progressive growth of the cell body, the origi 
nally simple cell metamorphoses itself into a plasmodium. Thus a 
young plasmodium was seen in which 1 of the 2 daughter nuclei 0% 
the host-cell had fallen apart into 2 granddaughter nuclei, while the 
myxosporidian nuclei had in the same time increased much more. In 
the next developmental steps of the plasmodium the number of the nuclei 
increases very rapidly, and with such increase their energy becomes ~ 
exhausted; the nucleoli vanish and the nuclear reticulum appears as a 
fine-grained granulation. Finally, the nuclear membrane shrinks and 
assumes an irregular contour. The cell nuclei then soon entirely vanish 
and we get a plasmode in which only myxosporidium nuclei are found 
With age the myxosporidia become displaced from the funicle and 
occupy the whole cavity. The zooid, thus become a myxosporidium- 
filled tube, closed at bothends. At this time the increasing mutual pres- 
sure produced by the continually growing myxosporidia results in their 
fusion to large plasmodes. Further growth produces rupture of the 
wall of the zooid and the myxosporidia come directly into contact with 
its chitinous investment. 
The morphological characters of the adult myxosporidium are here 
interpolated. 
Myxosporidium ? (structure of adult).— Naked, membraneless, amceboid- 
variable, size 20 to 200 4; form varying greatly with age, the youngest 
being globular, the older ones oval or lobulated from adaptation to 
external pressure-conditions. Ectoplasm perfectly transparent and 
hyaline. Nuelei very numerous, consisting of clear round vesicles 
showing in the fresh state round nucleoli. Applied against the out- 
side of (never within) each nucleolus is a small glittering globule. 
Pseudopodia formed by the ectoplasm, very fine, delicate and hair- 
like, ordinarily confined to a part and seldom covering the whole sur- 
face, often also forming small ramified tufts. Korotneff was unable to 
state whether the pseudopodia serve for attachment, but with the young 
myxosporidia the fixation to the funicle appeared really to oceur through 
these structures. 
Probably the direct influence of the water is injurious to them, and 
occasions a falling apart of the plasmodes and a freeing of the spores, 
which tien fill the spongy chitin-masses of the atrophied colony. In 
this state the spores remain the whole winter, and in April follows, prob- 
ably, the infection of the young Alcyonella (just out of the statoblast) by 
the amceba-brood from the spores. 
The time of the appearance of the myxosporidia corresponds with the 
development of the spermatoblasts, which ordinarily begins (around 
“Moscow) at the end of May, and the number of parasitic individuals 
increases pari passu with that of the spernatoblasts. While at the- 
