THK AERIAL ALGÆ OF ICELAND 



431 



Chlorellaceæ. 



Chiopella ellipsoidea Gcrn. Gerneck 1907, p. 250. Taf. XI, fig. 45-51. 

 Boye Petersen 1915, p. 331, Tab. IL fig. 27-30. Puymaly 1924, p. 207, 

 PI. IV. fig. 14-21. 



Chlorococcmn murorum Brand et Stocliniayer 1925, p. 329. Taf. 11, 

 fig. 1-10. 



N. W. Icel. 261 — S. Icel. 286, 395. 



That Chlorella ellipsoidea Gern. and Chlorococcam miiroram are one 

 and the same species scenis to nie quite obvious. Tiie descriplions of 

 the two species agree exactly except for a sliglit difference in the 

 dimensions of tlie cells. Tfie dimensions in this species being on the 

 wfiole very variable according to the age and development of the cells, 

 we can hardly attach any great importance to this difTerence. Another 

 and considerably more difficult question is that of the correct name of 

 the species. Brand has tentatively referred it to the old genus Chloro- 

 coccam I Fries) Grevillc emcnd. Brand is possibly right in his present- 

 ment of the various conceptions of the genus through the ages, but we 

 have no absolule certainty of Brands view being correct, and he has 

 undoubtedly made a mistake in placing the Xanthoria-alga in the same 

 genus under the name Chlorococciim sociabile. This alga bclongs quite 

 decisively to another genus, nay probably to another faniily, or it is 

 even remoter still. The two species difTer both in the structure of the 

 cell, especially the appearance of the chromatophore, and in the mode 

 of reproduction. Hence I prefer the current name of Chlorella ellipsoidea. 



In the two first-mcntioned samples from Iceland il grew on wood- 

 work, this being probably its habitual habitat. Puymaly has moreover 

 found it on tree-trunks and fungi (1 c). Brand has found it on stones 

 and walls (1. c). In Iceland I have likewise found well-developed spe- 

 cimens on walls (sample 395). 



Chlorella rugosa Boye P. n. sp. 



Chlorella cellulis ellipsoideis vel ovalibus; membrana cellularum 

 adultarum plus minus rugosa, chlorozincico jodurato coerulescente; chloro- 

 phora singula parietali sine pyrenoide. Bipartitionibus repetitis 4—8 ccl- 

 lulæ intra membrana materna oriuntur, una sæpe major quam ceteræ. 

 Cellulis vegetativis lat. 2,4— 6,6 //. long. 4,5— 11 ,u; sporangiis 

 lat. 6,4— 7,3 //, long. 7,9— 15,4// (v. s.). Fig. 35, 36. 



Hab. Ad ligna vetusta. 



W. Icel. 326, 349. 



This species shows great resemblance to Chlorella li- 

 china Chod. 1913, p. 92, fig. 83— 86), but diflers from this 

 species especially by the absence of pyrenoid in the chro- 

 matophore. Oil is often seen in the cells. but not starch. 

 In the young cells the wall is thin and smooth, later it 

 grows more or less papillose, sometimes over its entire 

 surface, sometimes only in certain portions of it. The walls 

 seem to consist of cellulose and colour strongly violet with Yj-om sample 

 chlor-zinc-iodine. Reproduction occurs by bipartition of the 349. (x 1200). 



Fig. 35. 



Chlorella 



riHiosa 11. sp. 



