90 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 
and no evidence in favor of Mingazzini’s supposition that the capsules 
represent the embryos, the filaments functioning as flagelle.! 
On the contrary everything that we know about the Myxosporidia 
favors the view that the embryo is not the capsule but the sporoplasm, 
the presence in it of nuclei, of a vacuole, and of amoeboid movements 
being quite conclusive. The most probable supposition in relation to 
the capsules is that they are accessory and temporary structures whose 
function is to secure attachment and perhaps a certain amount of 
motion, for the fulfillment of both of which objects they seem very 
well adapted. And it may be noted in passing that nematocystoid 
bodies are known which function for attachment, as well as those which 
function for stinging, ete.” 
Before discussing the mode of action of the filaments, a few words 
may advantageously be devoted to the relative functions of the spore 
and myxosporidium stages. 
(1) Dispersal is absolutely necessary to the species: This dispersal can 
take place only by the actual separation of myxosporidian individuals 
from one host and their migration to another, unless we adopt one of 
two very improbable suppositions, viz, either that they attach them- 
selves to the eggs of the host and await their development or that they 
develop in an intermediate host which feeds upon the fish.? 
(2) The spore is the means by which such dispersal is effected:+ Thus 
Lieberkiihn® saw some cysts ‘‘lost” and others opened, their contents 
escaping into the water. Also Ludwig and Railliet (p. 228) have 
observed the rupture of cysts in situ with escape of their contents. 
Thélohan® has seen the same occur with Glugea anomala; and in Myx- 
obolus ellipsoides he saw cysts shell out entire and burst.’ 
1 Mingazzini’s description given above implies very strongly this idea as to the 
function of the filaments, nevertheless he does not distinctly so state. Compare here 
Lieberkiihn’s statement (Bull. Acad. Roy. Belg., 1854, xx, pt. 2, p. 21) that the 
capsules, when extruded with the sporoplasm from the spore, show not the slightest 
trace of movement. ; 
2Jn the body epithelium of the Ctenophora we find peculiar adhesive cells with 
uneven and sticky surfaces. Their bases are prolonged into spirally coiled con- 
tractile filaments.—(Arnold Lang’s Text Book of Comparative Anatomy, London, 
1891, pt. 1, p. 82.) 
3The latter mode of change of host, though improbable, is not inconceivable. 
Still, everything seems to point toward the view that the whole life cycle from the 
attached spore in one generation to the liberated spore in the next, takes place in the 
same host. 
4The only place where this view is distinctly stated is the following (Mlle. 
Leclereq, 1890, Bull. Soc. Belg. de Microsc., xvi, p. 101): 
“On account of the presence of organs compared to nematocysts, but which seem 
rather elaters, one can believe that the spore is the disseminating form of the para- 
site, and that it can lead for some time a free life in the water.” [Italics my own 
for errors.] Here we again see the unfortunate results of the dual signification 0: 
the term ‘‘ filament.” 
5 Miiller’s Archiv., 1854, p. 356. 
6 Compt. Rend. hebdom. Soc. Biol. Paris, 1892, 1v, pp. 82-4. 
7Annal. de Microgr., 1890, u, pp. 203-4. The observation was upon a spore habi- 
tant on the tench (Myxobolus ellipsoides?). 
