THE MYXOSPORIDIA, OR PSOROSPERIvIS OF FISHES. 87 



the fact that at the same time he 'practically abandons'^ his vieic of the 

 adult nature of the ^^ psorospcrm^ 



Kuiistler and Pitres^ think that the capsules " appear to be true 

 nematocysts." 



Ludwig^ accepts the Leuckart-Biitschli attachuient theory, regard- 

 ing the tilaments as probably organs of attachment. He says that 

 thougli little is known as to the conditions under which filamont-extru- 

 sion naturally occurs, spores kept long in water extrude their filaments, 

 and adds: 



Probably the filaments serve for the attachiiiPiit of the spores, which have reached 

 the water through the opened tumors of the fish, to any. living or dead substances 

 vi^hatever. 



Thelohau'* comments upon Prof. Biitschli's view as follows: 



Biitschli, after having severely criticised that idea [Balbiani's antherozoid theoi'y], 

 compares them to nrticant organs. At the outset, as Balbiani observes, one can not 

 see what could here ba the rdte and the ntility of urticating organs. Further, the 

 filament of the polar capsules resembles but little those of the true uematocysts; 

 after their exit they present most often a sinuous aspect, sometimes neatly spiral, 

 which is far from recalling the appearance of the nrticant filaments which shoot out 

 abruptly from their capsules and present themselves under the form of rigid bayonets. 



Mingazzini* takes a totally different view from other authors and 

 one which it is impossible to reconcile with the present evidence. In 

 the following passage, besides other errors, the [capsular) filaments are 

 confounded with certain shell-processes {ribbonettes) described by Balbi- 

 ani in Myxobolus eUipsoldes, and further Biitschli's view (given above) 

 of the function of the filament is curiously distorted: 



Many observers have noted (in treating the myxosporidian spore with various 

 reagents) the exit from the polar bodies of a very long filament, which normally is 

 coiled within the polar body. As to the signification of this filament various opin- 

 ions have been emitted. Balhlani thinlis that it can serve as the organ of dispersal of 

 the spore, functioning at the maturity of the latter in a similar manner to the elaters of 

 the El aterium spore. Biitschli expresses the opinion that they can have' the signifi- 

 cation of nrticant filaments.'' But Balbiani has further observed that in the mature 

 spore these filaments are unwound and stand each around either the memhrane of its oivn 

 spore or around that of a neighboring spore, and supposes that in the last case the fila- 

 ments have the signification of copulating organs. Again, however, Biitschli, not 

 entirely satisfied with his first interpretation, has thought that the function of nrti- 

 cant capsules for a spore which has a membrane resistant to acids and alkalies, is a 

 kind of luxury, and that the filaments could serve to attach the spore to other fished 

 or to feed it [italics my own for errors]. 



From an analysis of the opinions it appears that none of them is entirely satis- 

 factory, while, in my opinion, from what I have seen of the gregarinoid forms, it 

 may be assumed that the polar bodies are nothing else than the embryos of the 

 Myxosporidia, homologous with the falciform bodies of the gregarine and coccidian 

 spores, on which view the filament of the polar body would Ije nothing else than 

 the tail of the gregarinoid form which remains inclosed in the polar body while 



' Journ. de Microgr., 1883, vii, pp. 198, 201, 276. 



2 Journ. de Microgr., 188t, viir, p. 474. 



^.Tahresber. d. rhein. Fisch.-Vcreins Bonn, 1888, p. 33. 



* Aunal. de Microgr., 1890, ii, pp. 207-208. 



6 Boll. Soc. Nat. Napoli, 1890, iv, p. 163. 



« See above (p. 86). 



