;<82 



JOIIS. IU)YK IM.TKHSKN 



Diploneis ovalis \:ir. oblongella Nii 

 Syn. I'l. 10, li-^. 12. 



K. Ici'l. L. 7. 8. 2 1. L. 2"). L. 77. 

 i;jo. IH). 2ir>. 217. 



Cl. Syn. 1, p '.);}. V. Hc-urck 

 L. 85. <)<). I,. 12S. I.. 129 - N. Iccl. 



Il has becn sliowii by H ri stol 1920 llint lliis form will withslaiul 

 intense desiccation. since it <^re\v alter gralting IVom a sample that had 

 been dried for 6^2 wecks. Iliistedt 1922. p. 98 nientions thai it oc- 

 enrs frecpiently in rock cavcs. Ostrii]) l'ound it in Iceland in 86 samples 

 from frcsh watcr. Four of the abovc-mentioned samples, in whicli I 

 found s|)ecimens of this form witii cell contents, were derived from 

 rocky walls. 



Caloneis C\. 



n 



FiR. 7. 



Cdloncis 

 nncitistiiHilvu 

 Bove F. n.sp. 



(X 1200). 



Caloneis angustivalva Boye V. n. sj). 

 E. Iccl. L. 41 — X. Iccl. L. 219. 



Caloneis valva lineari, apicibus rotundatis. long. 1 8,;3 //, 

 lat. 3,1//, striis 23 in 10//, radiantibiis, apices versus conver- 

 gentibus. Area apicali an^^usta. in media ])arle valvæ in fas- 

 ciam dilatata. Fig. 7. 



Found in two piaces on damj) ground, in one of the 

 piaces among Vaucheria, in the othcr among messes. A very 

 characteristic little species, which might jjcrhaps with ccjual 

 right have been referred to the genus Pinniihirid. 



Caloneis fasciata (Lagst.^ Cl. emend. Cl. Syn. 1, p. 50. 



If wc take this species in the same extension as (>lcvc (1. c' it is 

 a pronounced species collectiva embracing various probably (|uite distinct 

 forms. This was pointed out already by Hustedt 1909. p. 437 . Whcther 

 thesc forms should rightly bc conceived as separate species or merely 

 as varieties is not quile clear to me, so for the present I will regard 

 them as varieties. It is alniost impossible to find any information in 

 the litcraturc as to the occurrence of the individual forms, sincc the 

 authors as a rule give no particulars as regards the appearance of the 

 specimens observed. In the litcraturc the species is in the main stated 

 to belong to fresh water. more rarely it is menlioncd thai il may oc- 

 cur e. g. among mosscs (v. Schonfeld 1913) or in a rocky cave Hustedt 

 1922 II. Ostrup found it in 4(5 sami)lcs, while I have it from 20 sam|)lcs 

 in all. Hence il must be supposed to be most frc(picnt as an airial 

 alga, but evidently il will thrive bolli iii wnler and on land. 



The forms of this species found in Iceland may bc groupcd as 

 follows: 



1. Aj)ices subrostrate. 



a. Valve linear var. Uipicn. 



b. — slightly constricted in the miiidle . . — fonlindtis Grun.) 



2. ,\|)ices rounded. 



a. Valve linear var. iiiconsldnlissinia. 



b. — clliptic — i'lliplicd n. var. 



c. — lanceolate — fonticolu Grun.) 



