1861.] HYDROCHARIS MORSUS-RANiE. 31 



subaqueous bulbs. For what is a bulb ? To quote Balfour's 

 ' Class-book of Botany/ page 67, " It is a bud produced under- 

 ground, the centre corresponding to the axis, which is clothed 

 with scales, and which sends floAvering stems upwards and roots 

 downwards." Bulbs, like other buds, are formed upon or at the 

 end of stems. In general, these stems are reduced to a mere 

 disk, but there are very many cases in which bulbs are formed 

 at the end of long runners, an example of which is to be found 

 in the wild tulip [Tulipa sylvestris) , the bulbs of which are de- 

 scribed in the ' English Flora' of Sir J. E. Smith, as observed by 

 Mr. Ker, to be " formed at the extremity of lateral shoots of 

 a considerable length." Sir W, J. Hooker also, in his ' British 

 Flora,' notices " that the wild Tulip increases by throwing out 

 a long stout fibre from its root, at the extremity of which a bulb 

 appears." Anisunthus (Gladiolus) Cunonia, and several species 

 of Oxalis from the Cape, may also be cited as instances in point. 

 Here, then, in the Frogbit, we have a true bvlb, by means of 

 which it increases and continues permanently to live^ but it is 

 subaqueous, — a form of bulb not hitherto, it might seem, clearly 

 recognized. Secondly, the dispersal of the Frogbit is ensured 

 by means of the bulbs produced at the end of runners of some 

 length, and then detached in the autumn from the parent stem, 

 and moving freely with the gentle movements of the water in 

 which they lie, a fact worth noting. Thirdly, it is seldom that 

 the eye witnesses so distinctly as in the case of the Frogbit the 

 marvellous arrest of the decay affecting the whole of the rest of 

 the plant at the precise point at which it reaches the bulbs at the 

 extremity of the stems. There the vital force might be supposed 

 to become enfeebled and to fail, but, on the contrary, it is there 

 found to be stored up in all its wondrous energy, and there it 

 resists successfully the destruction which dissolves all else except 

 the little bulbous reservoirs in which it lies contained. Although 

 this wonder is repeated continually in other plants, very strikingly 

 in such as are of only annual duration, the seeds of which alone 

 survive the general decay, yet it is most plainly to be seen in this 

 analogous preservation of the Frogbit's bulbs. In the last place, 

 the return of the bulb of the Frogbit to the surface of the water 

 at the appointed time, in exact obedience to the law of its nature, 

 brings strongly into notice another of the surprising facts which 

 are scarcely adequately to be explained in the present state of 

 human knowledge. 



