M. A. Schneider on Opliiyocjstis Biitsclilil. 303 



contains only so imperceptible a quantity of liquid, that the 

 observation of the Ojjhryocystis in its natural medium is, or 

 seems to me to be, impossible. This is the first difficulty of 

 this investigation, which has many, that we cannot take the 

 parasite under the best conditions. I therefore added a 

 little salt water, a vehicle which I have often found to 

 succeed with delicate parasites, but with which it would be 

 difficult for me to say whether or not I have reason to be 

 satisfied in the present case. Not that this salt water intro- 

 duced the least apparent disturbance ; such as the Protozoa 

 were on coming into contact with it, such they remained ; but 

 it is this very persistence that troubles me, for I believe that, 

 in its proper medium, the Ophryocystis displays movements, 

 and that its form does not vary less than that of an Amoeba, 

 although perhaps very slowly. 



If we look over all these figures (tigs. 2-16), the processes, 

 some simple, others subdivided, are those of an Amoeba. 

 Every one will think that it is an Amoeban that I have 

 drawn, and the mind refuses to admit the immobility of these 

 pseudopodia. I refuse like the rest, but at the same time I 

 cannot say that I have seen them move. This reminds us of 

 the usual condition of the Myxosporidia ; it may be said that 

 this is the Myxosporidian phase of the Ophryocystis. 



Like the Myxosporidia*, in fact, these bodies are nakedj 

 without any envelope. The true Myxosporidia also present 

 an irregular contour bristling with processes, and, which is 

 remarkable, these processes in them are also so inert that their 

 nature is a subject of controversy. Lieberkvihn has seen feeble 

 amceboid movements in the species from the Pike ; Gabriel, 

 on the contrary, denies the assimilation to pseudopodia, sup- 

 porting his opinion upon the fact that if the faculty of emitting 

 processes exists (and it is clear that this cannot be con- 

 tested), that of making them return into the body is wanting. 

 Biitschli has ascertained that, under favourable circumstances, 

 the young Myxosporidia slowly move after the fashion of an 

 Amoeba. This being the case, that naturalist is inclined 

 to refer to the same cause all the processes with which 

 the body of these Sporozoa is furnished ; all are the result 

 of a slow but real contractility. I think that this is also the 

 case with the present Ophryocystis, and 1 believe that most 



* See N. Lieberkiihn, " Ueber die Psorosperiuieu," Arch. f. Auat. uud 

 Physiol. 1842, p. ll»3 ; B. Gabriel, " Ueber die in der Plarnbla^e des 

 Hechtes sich findenden parasitischeii Gebilde," Bericht d. sehles. Ue- 

 sellsch. 1879, pp. 2G-.'i3; O. Biitschli, " Zur Kenntniss der Fischpsoro- 

 spermieu,"' Zeitschr. L wiss. Zuol. vol, xxxv. ^18s0), pp. 629-661, 

 1)1. x.xxi, 



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