SCIENCE-GOSSIP. 



lOI 



endochrome had become quite divided in the 

 centre and the vacuoles of the new ends contained 

 three granules in each ; until now the active frond 

 had continued to slowly swing from and towards 

 the passive one (fig. 4). 



At fifty minutes from the division of the cell the 

 ends were about equal ; the vacuole of the passive 

 frond contained five granules, and that of the active 

 one three. The latter now had quite ceased to 

 swing from and towards the other ; it had, in fact, 

 become passive (fig. 5). 



Sixty minutes after the complete division, both 

 the new cells had lengthened and curved, so that 

 they closely resembled the normal fronds in form, 

 except being a little more slender perhaps (fig. 6), 

 When this alga is actively dividing, several pairs 

 may sometimes be seen on the same slide which 



a film of the C/csf^rnoK-bearing detritus, and exam- 

 ining this under a one-inch objective will not fail 

 to show some fronds 'in this state after a few repeti- 

 tions of the examination at the proper season. 

 Clcstei'iuin lunula is exceedingly common in the large 

 lake in Beech Park, near Hadley, along with C. 

 acei'osum, C. lineatuni, etc., and many beautiful 

 diatoms. 



The membrane of the Closteria is more or less 

 horny and often brownish, especially in the old 

 fronds, and is either smooth or marked with longi- 

 tudinal striae, as in C. strialatum ; this species was 

 very abundant in a little pond (or rather, puddle) 

 on Hampstead Heath, known locally as the Duck 

 Pond, and also in the Viaduct Pond in the same 

 locality. 



3, Cathcart Hill, London, N. ; July, 1896. 



Subdivision of Closterium lunula. 



Fig. I. — A frond just dividing x 350. a, active, and b, passive cells. 



Figs. 2-5. — Later stages of same x 200. 



Fig. 6. — Two perfect fronds x 100. 



have just completed this metamorphosis. The 

 temperature at the time of this observation was 

 about 16^ C. 



The vacuoles at the apices of the cells constantly 

 alter their places in the hyaline motile protoplasm, 

 and contain watery contents in which the minute 

 corpuscles rotate. The way they enter the vacuole 

 is very curious : at first they are seen to ap- 

 proach it and then are passed through its side, in 

 the same way as the ''sarcode" of the Amoeba 

 encompasses a food particle. 



But of 321 fronds of Closterium lunula examined in 

 October, 1895, there were only seven undergoing 

 this change, and when we consider that it requires 

 only a few hours to complete this division, after 

 which the fronds remain several days, or even 

 weeks, before they again subdivide, it is not sur- 

 prising that they are not more frequently observed 

 in this state. By having a large slide covered with 



Sunday Science Lectures. — The Select Com- 

 mittee of the House of Lords appointed to consider 

 the expediency of amending the Lord's Day Act of 

 17S1, has issued its report. This old Act enables 

 anyone to prosecute the promoters of Sunday 

 recreation, no matter how innocent, if conducted 

 at a profit to any person or body corporate. After 

 examining a mass of evidence their lordships point 

 out that the Act of 1S75 (38 and 39 Vict. c. So) 

 makes private prosecution improbable, as the 

 Crown has power to remit penalties and to quash 

 frivolous or vexatious prosecutions. Their lordships 

 think that, while the phraseology of the earlier .\ct 

 is now out of date, and its alteration, if practicable, 

 would be advantageous, the existing law. as laid 

 down in the two statutes, 21 Geo. HL, c. 49, and the 

 P-emission of Penalties Act, meets the sentiments of 

 the English people, and that any material change in 

 its general provisions might not be for public good. 



