LEMNACE-ffi. 21 



given to the microscopist, and the friend pointed out a part whicli he called the scales 

 as the portion at first put under the microscope. These tui-ned out to be no part of 

 the dodder, but the small withered leaves of another plant on which it had become 

 entwined, probably Sherardia, and belonging to tho raphis-bearing order Galiacece. 

 Professor GulUver tells us how he has grown from seed, in one pot of mould, plants 

 kno^vn as raphidian and exraphidian, and has been able to pick out each merely by 

 this character as soon as the seed leaves were well grown. " But nature," he says, 

 " requires much further questioning as to the constancy of raphides and their cells, 

 their significance and form, and the conditions under which they may or may not be 

 produced or checked, or modified in quantity or quality. A multipHcation of such en- 

 quiries would be easy and desirable in different locaUties, and a pleasant and instructive 

 addition to rural amusements." Professor Gulliver concludes his exliaustive paper by 

 remarking that above half the British monocotyledons appear to be devoid of raphides, 

 and he says, " In truth, how far the raphidian character may prove useful in the 

 revision many of the orders of plants seem to require, remains to be decided, after a 

 careful extension and con'ection of these observations, especially as regards tho ' Flora 

 of the World,' by judicious enquirers, who may have the requisite materials at their 

 command, and the will to use them, for the elucidation of the cjuestion of the value of 

 raphides and their cells, as natui-al characters in systematic botany. Meanwhile, it is 

 hoped that the present observations may induce some of our countrymen to study the 

 subject in their own flora." 



Dr. Lankester remarks that the biography of our British plants has yet to be 

 written, microscope in hand, and it is not tiU the minute details of the cell-life of each 

 plant have been recorded that we shall be in a position to arrive at the laws which 

 govern the life of the vegetable kingdom. And it may be added that, until due atten- 

 tion has been paid to this important subject, we shall never be able to comprehend 

 and realise all the mysterious plans and specifications by which Nature has marked, 

 for our instruction, her own affinities and contrasts, among alUed groups of tho 

 vegetable kingdom. 



Section IL— EU-LEMNA. 



Fronds floating, herbaceous, not tailed, each giving rise to a single 

 root-fibre, and furnished with naked baso-lateral clefts, from which 

 young fronds are produced, wliich remain sessile and attached only 

 for a short tune to the parent frond; cells of the epidermis bounded 

 by sinuous Unes. Flowers from a cleft in the margin of the frond. 

 Ovary containing a single semianatropous ovule. Fruit 1-seeded, in- 

 dehiscent. 



SPECIES n.-LEMNA MINOR. Linn. 

 Plate lilCCCXCV. 



BekJi. Ic. Fl. Germ, et Helv. Vol. VII. Tab. XIV. Fig. 15. 

 Billot, Fl. Gall, et Germ. Exsicc. No. 2939. 



Fronds floating, opaque, rather thick, flat on both sui'faces, oval- 

 obovate or suborbicular, entire, not tailed, subapiculate, the young 

 fronds sessile ; each frond giving rise to a single root-fibre, the under- 

 surface not spongy. 



