also the striation radiating from the micropyle. Only one specimen has been found. It is 

 figured side by side with a recent seed. 



Length 3.2 mm., breadth (crushed) 2.8 mm. Brunssum. 



BRASENIA TUBERCULATA Sp. nov. 

 PI. VL figs. 25-27. 



Semina ovalia, hilum versus parum latiora; testa granulata minuteve 

 tuberculata, embriotegam versus valde striata. 



Seeds oval somewhat broader towards the hilum, marked with one or more incon* 

 spicuous longitudinal grooves; testa granulate or minutely tubercled, strongly striate 

 towards the embryotega; embryotega (only partly preserved in one specimen) with 

 large micropyle; raphe broad and flat, only visible near the hilum. 



Length 3.25 to 4.0 mm.; breadth 2.5 to 3.0 mm. Brunssum. 



Compared with B. peltata the seeds on the average are considerably larger, and 

 are broader in proportion to their length. The most noticeable distinction however is 

 found in the minutely granular or shortly spiny exterior of the testa, which in the recent 

 plant is smooth, or only shows small flattened tubercles. The characteristic triradiate 

 cells of the genus can be seen under the microscope, but they are so masked by the 

 tubercles, and the shadows of the tubercles, that they do not show in the photographs. 

 The large-scale photographs of the apex of this species (fig. 27) and of B. peltata (fig. 23) 

 show clearly the differences. 



The Pleistocene forms of Brasenia seem to have been correctly referred to B. pel* 

 tata. Some badly ^preserved seeds of Brasenia, from a newly discovered Pliocene deposit 

 at Bidart, near Biarritz, sent to us by Professor Jules Welsch, appear to belong to 

 B. tubevculata; they are associated with Proserpinaca reticulata. 



NUPHAR CANALICULATUM Sp. nov. 

 PI. VII, figs. 1—3. 

 Semina ojjam ea N. lutei minora magisque globosa ; superficiei foveolae mi* 



NORES ET OB CELLARUM PARIETES CRASSISSIMAS MAGIS PERPLEXAE; CELLARUM PARIETES VICINAE 

 FOSSA CONSPICUA DISTINCTE SEJUNCTAE. 



Seeds smaller and more globose than those of N. luteum; surface pitting smaller 

 and more confused, owing to the great thickness of the cell* walls; adjacent cell* walls 

 distinctly divided on the surface by a channel which shows conspicuously. 



Length 4 to 3 mm., breadth 3 to 4 mm. Reuver, Swalmen. 



These seeds are abundant at Reuver, and one has been found at Swalmen. We 

 cannot refer them to a variety of Nuphar luteum. The difference of size and shape may 

 be of little importance, as these characters vary considerably in watersplants, according 

 to the conditions under which they live; but the very thick and conspicuously chan* 

 nelled ridge*like walls between the pits gives the seeds a very distinct appearance 

 under the microscope, and the character seems certainly to be of specific value. 



86 



