10 



Meconic ; and a vegetable alkali, named Narcotine, to which the unpleasant 

 stimulating properties are attributed by Magendie. Turner, 6. 47. 

 Exajviples. Papaver, Chelidonium, Eschscholtzia. 



V. NYMPILEACEiE. The Water Lily Tribe. 



Nymphjeaceje, Salisbury, Ann. Bot. 2. p. r 69.r(1805) ; Dec. Propr. Med. ed. 2. p. 119. (1816) ; 

 Syst. 2. 39. (1821) ; Propr. 1. 113. (1824) ; Lindl. Synops. 15. (1829.) 



Diagnosis. Polypetalous dicotyledons, with hypogynous stamens, con- 

 crete carpella, a many-celled ovarium, and ovula attached to the face of the 

 dissepiments. 



Anomalies. None. 



Essential Character. — Sepals and petals numerous, imbricated, passing gradually into 

 each other, the former persistent, the latter inserted upon the disk which surrounds the pistil- 

 lum. Stamens numerous, inserted above the petals into the disk, sometimes forming-, with the 

 combined petals, a superior monopetalous corolla ; filaments petaloid ; anthers adnate, burst- 

 ing inwards by a double longitudinal cleft. Disk large, fleshy, surrounding the ovarium 

 more or less. Ovarium polyspermous, many-celled, with the stigmata radiating from a common 

 centre upon a sort of flat urceolate cap. Fruit many-celled, indehiscent. Seeds very nume- 

 rous, attached to spongy dissepiments, and enveloped in a gelatinous arillus. Albumen farina- 

 ceous. Embryo small, on the outside of the base of the albumen, enclosed in a membranous 

 bag ; cotyledons foliaceous.— Herbs, with peltate or cordate fleshy leaves, arising from a pros- 

 trate trunk, growing in quiet waters. 



Affinities. There exists a great diversity of opinion among botanists as 

 to the real structure of this order, and, consequently, as to its affinities. This 

 has arisep. chiefly from the anomalous nature of the embryo, which is not naked, 

 as in most plants, but enclosed in a membranous sac or bag. By some, among 

 whom was the late M. Richard, this sac or bag was considered a cotyledon, 

 analogous to that of grasses, and enveloping the plumula ; and hence the order 

 was referred to Endogense, or Monocotyledons, and placed in the vicinity of 

 Hydrocharidese. By others, at the head of whom are Messrs. Mirbel and De- 

 candolle, the sac is considered a membrane of a peculiar kind ; and what Rich- 

 ard and his followers denominate plumula, is for them a 2-lobed embryo, where- 

 fore they place the order in Exogenee, or Dicotyledons. I do not think it worth 

 citing all the arguments that have been adduced on each side the question, 

 as botanists seem now to be generally agreed upon referring Nymphsacese to 

 Dicotyledons. I observe, however, that Dr. Von Martius adheres to the opinion 

 that Nymphaeaceae are monocotyledonous, and nearly related to Hydrocharide*. 

 See Hortus Regius Monaccnsis, p. 25. (1829.) Those who are curious to in- 

 vestigate the subject are referred to M. Deeandolle's Memoir, in the first 

 volume of the Transactions of the Physical and Natural History Society of 

 Geneva. In this place it will be sufficient to advert briefly to the proof that is 

 supposed to exist of their being Dicotyledons. In the first place, the structure 

 of the stem is essentially that of Exogense. See Mirbel's examination of the 

 anatomy of Nuphar luteum, in the Annates de Museum, vol. 16. p. 20 ; and of 

 Nelumbium, the close affinity of which with Nymphreaeeee no one can possibly 

 doubt, in the same work, vol. 13. t. 34. In both these plants the bundles of 

 fibres are placed in concentric circles, the youngest of which are outermost ; 

 but they all lie among a great quantity of cellular tissue : between each of 

 these circles is interposed a number of air-cells, just as is found in Myriophyl- 

 Ium and Hippuris, both undoubted Dicotyledons in the opinion of every body 

 except Link, who refers the latter to Endogenae (see Geivachsk. 6. p. 288). 

 Secondly, the leaves are those of Dioctyledons, and so is their convolute verna- 

 tion, which is not known in Monocotyledons, and their insertion and distinct ar- 



