QUARTERLY CIIRONICLE Ol' MICROSCOPICAL SCIENCE. 97 



Peritricha, viz. Dictiocystida, and Codonellida. Dicttjocijsta 

 has a fenestrated siliceous cell exactly like that of a Radio- 

 larian, of the Cystidan group, but the animal which hangs 

 from this basket is a ciliate Infusorian with large cilia on the 

 peristome. Codonella has a more delicate bell-like shell and 

 a very curious structure of the peristome. Nucleus and 

 vacuoles are figured in it. The species of these genera were 

 observed by Haeckel at Messina in 1859 and 1860, and 

 others at Lanzarote in 1866 and 186T. The species of Tin- 

 tinnus and Tintinnopsis described by Claparede and Lachmann 

 are representatives of the same interesting families. We 

 might most nearly, perhaps, indicate the condition of these 

 Infusoria to the reader by comparing them to a Cothurnia 

 or Vaginicola whose sheath has become detached from its 

 support, so that the animal now swims hanging from the 

 sheath like the tongue of a bell. 



A new Amoeboid Organism from Fresh Water, Pelomyxa 

 palustris. — In the same number of the same journal Dr. 

 Richard Greef, of Marburg, describes at length the very in- 

 teresting amoeboid organism which he was known to have 

 under observation, and for which he some time since pro- 

 posed the name Pelobius. This name was intended as a 

 pair to Bathybius, but has to be abandoned since it is in use 

 for an insect, and, moreover, the similarities between Pelo- 

 myxa and the structure known as Bathybius are not so clo:>e 

 as Greef at one time supposed. Pelomyza'xs, figured in three 

 plates, and, as its discoverer remarks, has great similarity to 

 the Plasmodium of some Myxomycetes, which it rnay very 

 possibly prove actually to be. It has been found in old 

 ponds at Popplesdorf, near Bonn, and also more recently 

 near Marburg. The amoeboid masses are large, often dark 

 brown in colour, protruding lobose hyaline pseudopodia. The 

 ground substance contains numerous nuclei, hyaline, homo- 

 geneous, highly refractive bodies, and delicate rod-like bodies. 

 Under certain conditions the Pelomyxa mass gives rise to 

 large swarms of minute Amoebse, which Greef followed in 

 some cases to a flagellate, freely-swimming condition. Greef 

 regards Pelomyxa as a multicellular, or, rather, multi- 

 nuclear amoeboid organism, allied to the Myxomycetes, but 

 to be classed under the Rhizopoda. 



News of Bathybius. — The reference which Greef makes 

 in his paper to Bathybius, and the continual references in 

 zoological writings to that ])rofounflly interesting structure, 

 makes it desirable to record the latest information which has 

 come to hand bearing upon that supposed organism. It must 

 be remembered that the Hathybius of today is not Huxley's 



Vol. xlv. — NEW sek. g 



