ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 861 



Infusoria are not true chlorophylls, analogous to the xanthophyll, 

 cyanophyll, and rhodophyll of algee. 



Action of Tannin on Infusoria.* — Eeferring to Mr. H. J. Wad- 



dington's paper on this subject (ante, p. 185), H. Gilliatt points out 

 that the effect of the tannic acid on Paramecium aurelia is to cause 

 the elongation and discharge of the trichocysts, which form a dense 

 fringe of slender rods all round the body. 



New Swiss Infusoria.^ — Dr. 0. E. Imhoff records in a prelimi- 

 nary communication the following new species of Infusoria from 

 Swiss lakes : — 



Dinoiryon divergens, so named on account of the manner in which 

 the individuals of the colony are grouped. Ceratiiim reticulatum, 

 nearly allied to C. hirundinella, but carries only two horns on the 

 posterior division of the test, Episfylis lacustris (no description at 

 present). Acineta elegans, test pear-shaped, length ■ 072 mm., maxi- 

 mum diameter of upper part * 044 mm. ; connected with the pedicle 

 by a globular inflation. Suckers numerous, arising at equal distances 

 from the feebly arched anterior surface. Imhoff remarks on the 

 incorrectness of the view entertained by previous investigators into 

 this subject, such as Forel, that the pelagic fauna of these lakes is 

 scanty, and limited to Copepoda and Gladocera. Besides the above 

 new species and six Botifera (for which see supra, p. 847 ), he is able, 

 from investigations made in the winter in the lakes of Ziirich, Zug, 

 ^ger, Katzen near Ziirich, Greifen, and Vierwaldstatter, to add 

 the following known forms to this fauna : — Dindbryum serfularia, 

 Peridinium tahulatum. 



New Peritrichous Infusoria. | — F. W. Phillips describes an 

 Infusorian nearly allied to the genus Gerda ( Vorticellina), and which 

 he names G. caudata : — 



The body is elongated, about seven times as long as broad, of an 

 undulating contour, subject to changes; it is highly contractile, 

 assuming a globular shape when retracted ; the integument is of a 

 reddish tint and transversely striate, annulate when contracted. The 

 posterior extremity of the body terminates in a peculiar imbricated 

 tail-like appendage, resembling the telescopic tail of a rotifer, but is 

 not telescopic ; this appendage is finely striate longitudinally ; the 

 body when extended, before the ciliary disk is projected, is broad and 

 rounded at both ends and depressed in the middle. The ciliary disk 

 is convex , the peristome border thick ; cilia very fine and long ; 

 vestibular set^ distinct ; contractile vesicle spherical, situated at the 

 extremity of the vestibular cleft ; minute non-contractile vesicles dis- 

 tributed throughout the whole of the parenchyma ; the endoplast is 

 spherical and conspicuous ; endoplasm granular, and maintains a con- 

 tinual cyclosis or circulation. The eversion of the cilia is extremely 

 gradual, occupying about five to ten minutes ; retraction is instanta- 

 neous. W. Saville Kent points out an analogy between the tail-like 



* Pioc. Linn. Soc. N. S. Wales, 25th July, 1883. 



+ Zool. Anzeig., vi. (1883), pp. 466-71. 



X Journ. Linn. Soc. Lond.— Zool., xvii. (1883) pp. 293-5 (4 figs.). 



