20 



Actinella Lewis. 



1. Actinella Guianensis Grun. in litt. 



Of the genus Actinella only one species, the A. punctata Lewis from White 

 Mountain Deposits, is known. The genus, which is nearly related to Eunotia, is distin- 

 guished by the diöerent development of the ends. The puncta, which foUow the mar- 

 gins of A. punctata as well as of A. Guianensis, are also visible in true Eunotia, for 

 instance E. denticulata BrÉb. 



The Actinella Guianensis, which occurs rarely in Cl. et Moll. Diat. N:o 212, is 

 larger than A. punctata and has 14 — 16 strite in 0,01 ram., varying in difierent parts 

 of the valve. 



Length of frustule 0,105 mm. Breadth of one end 0,007 of the other 0,011 mm. 



.' Pl. V, fig. 58, "">'/,. 



Brazil, Caldas on mosses (Dr. Hj. Mosén). 



Asterolampra Ehb. 



1. Asterolampra Balearica Cl. N. Sp. 



Rays about 10, not reaching the margin of the disc. Umbilicus small, the dia- 

 meter being only V4 — Vs ^^f that of the disc. Umbilical rays are straight and not 

 branched. The corapartments are covered by cellules arranged into lines, crossing each 

 other in three directions, 9 in 0^01 mm. 



Diameter of the valve 0,0715 mm. 



Balearic Islets extremely rare (F. Södeklund). 

 Pl. V, fig. 59, a. "y„ b. a compartment "°7i. 



This species appears to be related to Asterolampra Grevillei Wallich, which also 

 occurs in the Balearic gathering, but this species has much finer cellulation (20 — 22 

 lines in 0,01 mm.). The A. centraster Johnst. Micr. Journ. VIII, p. 12, Pl. I, fig. 10 

 is more nearly related, but its umbilicus is lai'ger. 



Coscinodiscus Ehb. 



1. Coscinodiscus undulatus Cl. N. Sp. 



The surface of the disc elevated in the middle and with an elevated ring half- 

 way between the centre and the margin. Surface covered with dense, pearllike puncta 

 arranged in lines radiating from the centre to the margin, where they become smaller, 

 much more crowded and form short strias. 



Diam. 0,096 mm. 



Pl. V, fig. 60, a. "7i) b. ^"Vi outline of a valve in oblique position. 



