240 PROCEEDINGS COTTESWOLD CLUB 1914 



First, it occurs frequently in Ireland, in counties Limerick, 

 Clare, Galway, Dublin, Meath, Fermanagh, S. Donegal, 

 Armagh, Down, Antrim, and Derry ; i.e., it is most frequent in 

 Ulster, and is unrecorded from the extreme West, and from 

 the whole of the S.-E. of the Island. In England it is known 

 only on the WeUand at Peakirk, along the Trent at various 

 spots in N. Lincoln, and at one place in Derbyshire, on the 

 Canal at Renishaw. 



Secondly, it constantly differs from both H. nodiflorum 

 and H. inundatum, and it is fairly intermediate between the 

 two. It has e.g. a style and foliage and general habit, as well 

 as several minor points, which, on the whole, come just there, 

 and it is always (I believe) found in the immediate vicinity 

 of the two commoner species. 



Thirdly, within the limits so marked out, it varies enorm- 

 ously ; L ometimes it is much nearer inundatum in habit and 

 in cut of foliage, less often very near small H. nodiflorum. 

 " Taking two well-contrasted forms, say that from Tuam, 

 N.-E. Galway . . . and that from Portumna, S.-E. Galway 

 ... we might illuminate the subject by naming them respec- 

 tively f. suhinundatum and f. subnodiflorum . The former is, 

 indeed, much larger than most inundatum, and the latter 

 smaller than most nodiflorum. But the foliage of the former 

 is clearly near that of inundatum ; it is broader and longer 

 in all its parts and as a whole ; capillary segments become 

 linear, lobes are larger and broader, and even tend to merge 

 into each other ; but it is of essentially the same character. 

 The texture of this form is more that of a water-plant, whereas 

 in f. subnodiflorum the texture reminds one of small dry land 

 (or mud) forms of nodiflorum. This latter form of Moorei 

 has the leaflets far less cut : in the upper leaves they are very 

 near nodiflorum in character, but in the lower leaves are 

 strongly toothed or lobed. The floral characters separate it 

 from nodiflorum." — [Irish Nat., Jan., 1914, p. 7) 



This and other reasons, summarised below, led me in the 

 teeth of the opinion of better botanists than myself, especially 

 Mr Druce, of Oxford, and Prof. Gliick, of Heidelberg, to 

 decide that the form is probably the hybrid of the two common 

 species. My reasons are based on the usual phenomena of 

 hybrids : — 



