ALGOLOGICAL NOTES 



85 



widely distributed in the British Islands, but up to the present 

 this is only the third record of the occurrence of Bichteriella 

 hotryoides. 



5. Lagerheimia wratislawiensis Schroder in Bar. Deutsch. 

 hot. Ges. 1897, xv. p. 373, t. 17, f. 7. This Alga occurred sparingly 

 among numerous members of the Protococcales in a small pool in 

 the grounds of Studley Castle, Warwickshire, in October, 1906. 

 It is, perhaps, the most distinctive species of the genus, and this 

 is the first British record. In no single instance did the parietal 

 chloroplast possess a pyrenoid, and, therefore, after comparison 

 with Schroder's original description and figure, this must be 

 regarded as additional evidence that the presence or absence of 

 pyrenoids in the chloroplasts of the Protococcales is largely a 

 question of nutrition. Long. cell. 12 /x, lat. cell. 9 /x ; long. set. 

 30-31 fx. (Fig. 2, G.) 



6. Lagerheimia genevense Chodat in Nuova Notarisia, 1895, 

 p. 87, f. 1-12. This minute Alga of the subfamily PhytJieliecB 

 occurred in the helioplankton of Blackroot Pool, Sutton Park, 

 Warwickshire, in August, 1907. The cells were cyhndrical, but 



Fig. 2. — A, Lagerheimia (jenevense Chodat. B-F, L. genevense var. suh- 

 glohom (\ lenww.) GhoA. \ C-F, stages in formation of autospores. G, L.xcratis- 

 laiviensis Schroder. A and B, x 1000 ; C-G, x 500. 



proportionately a little shorter than those figured by Chodat, and 

 the bristles were rather short. Long. cell. 8 ju, lat. 4-5 /x ; long, 

 set. 7-8 IX. (Fig. 2, A.) 



Var. suBGLOBOSA (Lemm.) Chodat, Algues vertes de la Suisse, 

 Berne, 1902, p. 188. Lagerheimia subglobosa Lemm. in Hedwigia, 

 xxxvii. 1898, p. 309, t. 10, f. 9. I agree with Chodat that this 

 form can scai'cely l)e regarded as a species, as it differs only from 

 L. genevenne in its ellipsoid cells. It occurred in the helioplankton 

 of i3racebridge Pool, Sutton Park, Warwickshire, in April, 1910 ; 

 and also in quantity in a small pool in the grounds of Studley 

 Castle, Warwicksliire, in October, 1906. From the last-named 

 locality many of the examples showed the formation of autospores, 



