FRESHWATER AL<Uv 51 



Genus NAVICULA Bory. 

 80. NAVICULA MUTICOPSIKOUMIS. 

 Hit/tii-ojisifonni' W. and <J. S. West, u/>. fit., p. i'8K PI. XXVI., fig. 1:11. 



Long. valv. = 12 '5 /*; lat. valv. = 5'5/j.. 



I liitt. Freshwater pond, Granite Harbour, January 20th, 1902 (rather rare). 



81. NAVICULA SEMIXULI M. 



(PI. II., figs. 97, 98.) 



Navifula Seminiili.ini (')run., Verlmndl. k.k. zool.-bot. Ges., Wien (18i!o), p. ">.">:>, Tub. II., fig. -2 ; Van 

 Heurck, Synods. Diat. Bulg. (18,s.i-,s:, ,, p. m;, PI. XIV., fig. !). 



Long. valv. = 1G-20/A; lat. valv. = 4'5-5/M. 



I lull. On ice, four feet above fro/en watercourse through " Penknife ice," McMimlo 

 Bay, September 13th, 1902 ; pond in ice, off Black Island, Mc.Murdo Strait, December 

 31st, 1902 ; in freshwater ice under boulder, Cape Adare, January 9th, 1902. 



The valves of this fairly common form were obviously swollen in the middle, and 

 very gradually tapered from there towards the two ends, which were occasionally vn-v 

 faintly capitate. The stria? were in many cases a little further apart in the middle of 

 the valve than elsewhere, in which respect the specimens approached A 7 , minium Grim., 

 but the shape of the valve in this species is rather different. 



82. NAVICULA MUTICOPSIS. 



Navicula miittcopsis Van Heurck, Diatomccs, Result, d. voyage du S.Y. ' Btlgira ' (I'.Hi'.i), p. U', PI. II., 

 fig. 181. 



L<mg. valv. = 13-25 /A; lat, = 7-9 /x. 



Ifdfi. Pond, Cape Adare, January 9th, 1902 ; on ice, McMunln Bay. Sc-ptembrr 

 13th, 1902; pond in ice, off Black Island, McMurdo Strait, December 31st, 190-J : 

 Gap pond, Winter Harbour ; freshwater pond, Granite Harbour ; pond in eskers upon 

 ice, half-way between Black and Brown Islands, January 3rd, 1903 ; in ice, under 

 boulder, Cape Adare, January 9th, 1902. 



This is certainly one of the most widely distributed of Antarctic Diatoms. Both 

 of the forms recorded by Messrs. West (<y. fit., pp. 'JS:', L'Sl) were of wide occurrence. 



83. NAVICDLA CYMATOPI.KURUS. 



(PL II., fig. 101.) 



Navirula cymatnphum W. and G. S. West, op. rit., p. :>8:>, PI. XXVI., tigs. 1:1:5. m. 

 Long. valv. = 24-30 p ; lat, valv. = 4-5 5 /i. 

 llnli. On ice, four feet above fro/.en watercourse, through " Penknife ice." 



