SCIENTIFIC COMMITTEE. 



CXV 



Pancratieae, on the other, by the absence of either corona or staminal 

 cup. However, traces of a corona can be discerned in several members 

 of the genus Hippeastrum indigenous to the Organ Mountains of South 

 Brazil. In H. calyptratum this organ is well developed, and it 

 is interesting to observe the changes which occur when this species 

 is used as a pollen parent in hybridizing. 



"In H. vittaium, the throat of the tube is not ringed with any 

 visible corona, although a ring of red pigment is usually present. In 

 place of a corona there are tufts of whitish hairs,* and so the throat 

 in H. vittatum is said to be ' bearded.' In the hybrid all three 

 characters are present in modified forms. In place of the continuous 

 corona of the male parent there is an interrupted ring of processes in 

 various degrees of relief, coloured red, and crested with tufts of ruddy 

 and whitish hairs. 



This interesting structural change follows the law which I have 

 observed in all interspecific hybrids which have come under my own 

 observation, i.e. that the characters of the hybrid show a balance 

 between those of the parents. If they do not constitute an 

 approximate mean between the parental extremes, they at least 

 hold some position comprised within these extremes. 



" I have found no instances of absolute dominance or recessivity 

 in the characters of interspecific hybrids." 



Scientific Committee, June 3, 1914. 



Mr. A. E. Bowles, M.A., F.L.S., F.E.S., in the Chair, with eight 

 members present, and Mr. W. R. Dykes, visitor. 



Fungus attack upon Nymphaea. — Mr. J. R. Ramsbottom reported 

 as follows upon the fungus attack on foliage of Nymphaea : 



" A leaf of Nymphaea sent to me by Mr. Bowles, and exhibited 

 at the last meeting, showed two rows of large holes parallel to the 

 midrib. An examination of the decayed tissues showed fungus 

 spores, together with certain algae, diatoms, &c. The fungus proved 

 to be one of the Hyphomycetes. It was first described by Allescher in 

 1895 as Ploeosporium nymphaearum. He had gathered it on hving 

 leaves of Nymphaea alba, flava, odorata, and Nuphar luteum in the 

 Munich Botanic Garden. Bresadola had the fungus sent to him 

 from Brandenburg, and, not realizing he had the same fungus as 

 Allescher, described it under the name Ramularia nymphaeae, later 

 as Ovularia nymphaeae. Allescher afterwards pointed out that the 

 fungi were identical, but that owing to having had old specimens 

 he had been misled by the tearing of the epidermis of the host plant 

 caused by the rapid growth of the fungus. He holds that Ovularia is 

 the correct genus, and, of course, the first specific name, nymphaearum, 

 must stand. Judging from the specimens I have seen, Ramularia, 



* Perhaps these hairs may not be invariably present in H. vittatum (true) 

 Twenty-five years ago I noted an unbearded specimen, but the male parent of 

 this hybrid here described is bearded. 



