part 2] PREGLACIAL FLORAS FROM CASTLE EDEX. 113" 



Sparganium ramosum, were found. One of these, which ,was 

 highly pyritized, decayed and fell to pieces. 



Length = 3'7 mm.; breadth = 2 - 2 mm. 



S. ramosum ranges throughout the Northern Hemisphere. 



POTAMOGETONACE^. 



Potamogetox acittifolius Link. (PL VII, tig. 2.) 



Three specimens belong to this species. The recurved style 

 distinguishes it from P. triclioides, in which the style is directed 

 forward. 



Length = 2*3 mm. ; breadth = 2 mm. 



The species occurred in the Pliocene of Tegelen in Holland. 

 It is an inhabitant of the British Isles, though rare, being found 

 only on the eastern side of the country from Aberdeen southwards. 



Its present distribution is throughout Europe, the Caucasus, and 

 Australia. 



Potamogetox pectixatus Linnaeus. (PL VII, fig- 3.) 



Four specimens agree in every way with this species. 



Length = 3 - 5 mm.; breadth (before germination) =2 - o mm. 



The species was found both in the Teglian and in the Cromerian. 

 Its present distribution is throughout both northern and southern 

 temperate regions. 



Potamogetox xataxs Linnaeus. (PL VII, fig. 4.) 



A single nut agrees in every way with the species. 



Length =3 mm. ; breadth=2"7 mm. 



This species occurs in the Cromerian. At the present day it is 

 widely distributed throughout the Northern Hemisphere, and occurs 

 also in Australia. 



POTAMOGETOX Sp. -1. ( PL VII. fig. 5.) 



Nut ovate, inflated, with small central depression ; ventral margin 

 convex above, concave in the middle, having a downward-directed 

 spine, near its base; dorsal margin convex; attachment basi-ventral; 

 style subapical, recurved ; keel reaching almost to the style,. 

 smooth, convex transversely. One specimen. 



Length = 2*8 mm. ; breadth = 2 mm. 



I am unable to identify this species. 



POTAMOGETOX sp. 5. (PL VII, fig. 6.) 



Nut ovate, inllated, central depression very broad and shallow ; 

 ventral margin convex above, straight below; dorsal margin convex; 

 attachment basal ; style very small, slender, recurved ; keel not 

 reaching the style, having a strong median ridge, but depressed so 

 that the edges of the nut form ridged margins ; the keel, the 

 ridged margins, and the median ridge together give rise to channels 



