82 SUMMARY OF CURRENT RESEARCHES RELATING TO . 



anterior extremity, which is furnishccl with three vibratilo flagella. 

 A narrow, rapidly iinrlulating membrane extends along the entire 

 length of one lateral border. From the terminal margin of this 

 membrane a long thread-like filament springs, and follows the 

 undnlations of the tissue to which it is attached. 



Chilodon mcgalotrochce n. sp. is an ectoparasite of the social 

 rotifer Megalotrocha. 



Flagellate Infusorian parasitic on Trout.* — L. F. Henneguy 

 describes in detail a new ectoparasitic flagellate infusorian which has 

 been the cause of disease among young trout ; it has now been seen 

 for two seasons, but it has been found that there is a decrease in 

 mortality when the young trout are placed in an aquarium through 

 which a rapid current of water passes. Tlie essential points in the 

 structure of Bodo necator have been already noted.f 



New Rhizopod. J — J. Kiinstler describes a new form found in some 

 OphelicB at Arcachon. It is somewhat elongated, pointed at either 

 end, and has on each side psoudopodia of some length. In its middle 

 there is a dark axial rod, which is intensely coloured by mcthylene- 

 green ; this rod is formed of a stratified substance, and is bifid or 

 multifid at its extremities ; its surface is often spotted with small 

 knobs, which elongate, and becoming gemmiform detach themselves 

 from the rod and pass into the peripheral protoplasm. Here each 

 corpuscle becomes surrounded by a special protoplasmic layer. 



The rest of the body has the form of a flattened protoplasmic 

 lamella, divided into a central denser region, and a peripheral which 

 is greatly vacuolated, so as to recall the substance of the body of 

 certain Eadiolaria. The pseud opodia, though apparently rigid, are 

 capable of contracting and becoming pyriform in shape. Though 

 they resemble those of the Eadiolaria in their rigidity and rectilinear 

 direction, they are distinguished from them by their thickness, struc- 

 ture, and localization at the sides of the body. The fluid within 

 contains small rounded bodies with a central corpuscle ; these take 

 on the form of the adult, and appear to be derived from the gemmas 

 formed on the central rod. 



Ophryocystis biitscMii. § — To our notice of A. Schneider's pre- 

 liminary communication || on this subject, we may add some remarks 

 drawn from the fuller memoir now published. Ophryocystis differs 

 remarkably from other Sporozoa in that the amcebiform stage pre- 

 sents us with " un luxe de prolongements " and a facies altogether 

 different to that of any known Sporozoon. The possession of a large 

 number of nuclei in these amceboid forms has its analogue in certain 

 Amoebina, and distantly in the Myxosporidia. Conjugation of two 

 always uninuclear individuals has been observed, but conjugation is 

 not known among the Coccidia, and this peculiarity allies Ophryocystis 

 to the most differentiated Gregarines. The mode of sporulation allies 



* Arch. Zool. Expe'r. et Gen., ii. (1884) pp. 403-11. 



t See this Journal, iii. (1883) p. 379." 



X Coraptcs Eendus, xcix. (1884) pp. 337-8. 



§ Arch. Zool. Expe'r. et Gen., ii. (1884) pp. 111-26 (1 pi.). 



II See this Journal, iii. (1883) p. 522. 



