214 The Waterlii.ies. 



is, as now constituted, the most widespread species ; it extends from 

 Siberia through Kashmir and China to Australia (?), and is known from 

 Granite, Idaho, and Ontario Province, Canada, in North America. N. lotus 

 is also very widespread, but further investigation is needed to determine 

 the relation of the various forms. In N. thermalis of the warm springs of 

 Hungary we have its most northern representative. And its existence 

 here is a problem of extreme interest. The Grosswardein locality was 

 first recorded by Waldstein and Kitaibel (1802). Plants were removed 

 from there by Paul Kitaibel in 1800 and planted in the warm springs 

 of Lucasbad at Budapesth. In the former place the temperature of the 

 water is 33.75 to 41. 25 C, and the water is quite pure; at the latter 

 station the water is only 26 C, and is charged with sulphur and other 

 mineral matters. Nevertheless the plant grew equally well in both places, 

 and flowered freely from May to October. The Lucasbad station was, 

 I believe, destroyed by building operations about 1890 (Schilbersky, 1889). 

 Kitaibel, Boissier, Neilreich, Kerner, Engler, and Simonkai (1890) con- 

 sidered N. thermalis as identical with A^. lotus of Egypt, but Simkovics 

 (1883) agrees with DeCandolle in pronouncing it a distinct species. If 

 it could be shown, as some have believed, that the plant was originally 

 introduced here by man, perhaps by the Turks, the question of identity 

 would be settled. But Simonkai considers this theory impossible, since 

 the plant was of no material use; and Staub (1891)' agrees that it is 

 almost certainly a relic of a pre-glacial vegetation, when the whole of 

 Europe enjoyed a comparatively warm climate. When the plants of this 

 period were driven back toward the equator by colder conditions, this one 

 remained in the favorable temperature of the thermal springs. Along 

 with it has continued a snail, Melanopsis parreyssi Muhlf., very near of kin 

 to M. costata Fer. of Egypt. According to Staub, the genus Melanopsis 

 was common in Europe in the Drift period ; and he considers that the 

 warm springs of Grosswardein are older than the Drift. It is also notable 

 that there were in recent geological times throughout Europe waterlilies 

 resembling the Lotos group (Schenck, 1888 ; Staub, 1. c.) which may have 

 been the ancestors alike of the Egyptian and the Hungarian plants. There 

 are the best of reasons, therefore, for considering N. thermalis as truly 

 native in its present habitat. And if we can believe that its specific char- 

 acters were demarcated as early as the Drift period, and have not changed 



1 It must be noted that Staub's paper, as it appears in Engler's Jahrbuch, is full of the most 

 egregious errors concerning the relationships and distribution of living species of Nymphaea; we 

 hope they are misprints ! 





