480 



HUTTONIA. 



1 



GENUS 139. 



HUTTONIA, GROVE & 



STURT, 1887. 



Valve showing two alternate 

 elevations or ocelli. 



This genus appears intermediate 

 between the Biddulphiece and the 

 Eupodiscice, and requires further 

 examination. The figure in the 

 text is of H. alternaus, Gr. and St., 

 from one of my photographs. This 

 diatom is found in the deposit of 

 Oamaru. 



Fig. 213. Huttonia alternans. 



GENUS 140. GROVEA AD. SCHMIDT, 1890. 



Valve discoid, showing 7 

 to 8 mammiform-ocelliform 

 marginal elevations, between 

 each of which is an obtuse 

 rounded marginal projection, 

 placed lower than the pre- 

 ceding, and apparently turned 

 in an opposite direction. 

 Centre occupied by a broad 

 umbilicus surrounded by a 

 clear space communicating 

 by clear radiant spaces with 



Fig. 214. -Graven fedaiis. the margin of the valve, 



intermediate portions very delicately punctate and bearing here 

 and there coarse puncta. 



The figure in the text is Gr. pedalis (Gr. and St.) Ad. Schm., having its 

 origin in the Oamaru deposit, and which Messrs. Grove and Sturt described 

 under the name of Biddulphia pedalis, a name also adopted by Grunow. I, 

 however, find this diatom differs sufficiently to justify the name given it by 

 Dr. Ad. Schmidt. 



