HARDWICKE'S SCIENCE-GOSSIP. 



"5 



plants. In the same year, apparently at a somewhat 

 earlier date, it was discovered in Ireland, and de- 

 scribed under the name of Podosphara Haekeliana, 

 by the British naturalist W. Archer, who subse- 

 quently recognised it as the C. elegans of Cienkowski. 

 Later on it was met with, and carefully studied, by 



Clathrulina belongs. Finally it was found in New 

 Jersey and in Pennsylvania, in North America, and 

 figured with diagrammatic clearness by the American 

 naturalist, Dr. Joseph Leidy. In 1879, a second 

 species of Clathrulina was described by C. von Me- 

 reschkowski, and named C. Cienkowski, after the 



Fig 76. — Clathrulina elegans. (A), as viewed with a 

 one-sixth objective. 



Fig. 75.— (D), a finely-developed, but not unusual form of 

 H. pellucida. 



Fig. 77.— C. elegans. (E), a dark and probably old specimen. 



Professor Haeckel at Jena, Professor R. Greef, and 

 Professors Hertwig and Lesser at Bonn, all of whom 

 have published valuable observations upon it, and 

 upon its relations to other Protozoa, especially the 

 three last named, whose papers are most valuable 

 contributions to our knowledge of the group to which 



Fig. 78. — C. elegans. (C), an active organism with a 

 protoplasmic veil and numerous threadlets. 



original discoverer and describer of the genus. This 

 truly beautiful and elegant species, which was found 

 in the Lake of Onega, near Powenetz, is readily dis- 

 tinguishable from its congener by its spiny shell, 

 which gives off from the small triangular area be- 

 tween every three of its holes a short, blunt, and 



