INVEETEBKATA, CRYPTOGAMIA, MICROSCOPY, ETC. 845 



or two oogouia a single autlieridium, or even two or three oogonia two 

 antheridia. The production of zoospores was not observed by 

 Woronin. He considers the new species to be most nearly allied to 

 V. geminata, and believes that, like that species, it may assume a 

 (row^ros/ra-condition, and hence occur also in an amoeboid state. 



Parasitic Nostoc* — Several Algte belonging to the group of 

 Nostochineaj enter and live in the tissues of various terrestrial or 

 aquatic plants, and an additional instance of this has just been 

 observed by M. L. Marchaud, which he reports on account of its 

 singularity. 



He collected on the edge of a ditch near Montmorency, some 

 small flask-shaped bodies, of a blackish-green colour, ovoid, cylin- 

 drical or like commas, from • 1 to 1 • 5 mm. in height, which were fixed 

 to the ground by branched radicular filaments. They vegetated on 

 the damp soil intermixed with numerous specimens of Pottia (Gijmno- 

 stomum triincatuliun), Anthoceras levels, JRiccia glauca, Jungermannia 

 tenuis, &c., and in some places covered the ground. They are repro- 

 duced each year, disappearing in winter to reappear in the spring. 



These seemed at first to be young individuals of Botrydium 

 granulatum ; but when examined under the Microscope they presented 

 an entirely unusual character. Instead of being lined with a layer 

 of granular chlorophyll, the interior of the ampulla was lined with 

 a network of moniliform filaments presenting all the characters of 

 chajilets of Nostoc or Anahcena. 



The author discusses the probable nature of these singular bodies, 

 which, though further examination is yet required, he is inclined to 

 believe are due to one of the Nostochineaj (Anahcena ov Nostoc), which, 

 having penetrated into the radicular filaments of a moss or Hepatica, 

 and there developing, cause a considerable local swelling of the 

 neighbouring wall. 



Movement of the Cell-contents of Closterium lunula. f — Mr. 

 A. W. Wills jioiiits out that at each cud of the fronds of certain 

 Desmidiea3 there is a clear oval or spherical sjmcc, within which arc 

 seen a number cf minute particles in more or less active motion, at 

 any rate during some periods of the life of the plant. This is 

 especially the case in the genus Closterium, and conspicuously so in 

 the largest species, Closterium liinuJa. 



In this plant tlierc is also, as lias been often observed, a certain 

 motion of the colourless granular liquid cell-contents which form a 

 thin film between tlie deep-green eudochrome mass and the cell-wall 

 of the frond. This motion has been described as a circulation, but 

 the term is incorrect. The actual character of the movement is ono 

 of ebb and flow, alternately towards and from the ends, and, in 

 favourable specimens, careful examination under a ;J or ,1 objective 

 shows tliat it takes place in delicate longitudinal lines or bands, and 

 that in different lines the flow may be actually in 02)posite directions 

 at the same time, while in any one lino the direction of flow is usually 



♦ ' Hull. Soo. Bot. Fninoo," xxvi. (1870) p. 336. 

 t 'Mull. Nat.,' iii. (1H80) j), IsT. 



