ROSACEA. 



361 



single piece ; but they are really made up of numerous little leaflets 

 crowded together, and as it were piled up on one another, being kept 

 in contact by the velvety down with which they are covered. 



Those Ivesias which, like /. lijcopodioideH^ have only five stamens 

 are in that respect analogous to Sibbaldid- (figs. 4'23-427), which 



Potentilla {Sibbaldia) proctcmhens. 



Fig. 42 1. 

 LoiiKitudinal section of flower. 



Fig. 426." Fig. 425. Fig. 427. 



Carpel. Multiple fruit. Longitudinal section 



of carpel. 



comprises small plants from the temperate regions of Europe and 

 Asia, and the arctic regions of xVmerica, possessing the androceum of 

 Pofeniiiia penfandra, with the habit, foliage, and floral organization^ 

 of very many alpine species of FoientUla, from which it is impossible 

 to separate them. Nor is Bryadanfhe' more distinct; it is a species 



^ A. Geay, Proc. Amer. Acad., loc. cit., 531, 

 n. 4. 



2 L., Gen., n. 393.— J., Gen., 337.— G^etn., 

 Fruct., i. 348, t. 73.— DC, Frodr., ii. 586.— 

 Bung., Ledeh. FT. Alt., i. 428 — Ledeb., Inn. 

 Fl. Moss., t. 276.— Ekdl., Gen., n. 6367.— 

 BoTLE, lllustr. Himal., t. 40, fig. 5. — Jacquem., 

 Voy. Bot.,i.&l. — Walp., Rej]., ii. 37; Ann., 

 i. 269. 



^ The androceum may consist of ten st:imens, 

 but it is usually iso.-tcmonous. Tiius in tlic 

 flowers of S, cuneata Kze., there are only five 

 Btiimens, alternipetalous, with introrse anthers, 

 and filaments inserted round the edge of a glandu- 

 lar disk lining the porringer-like receptacle. This 

 disk has five cusps, where the petals, articulated 



at the base, are inserted ; while the stamens are 

 inserted at the middle points of the concave 

 edges. The filament, too, is articulated with 

 the anther. The surface of the disk is covered 

 with hairs between the stamens and the gyna?- 

 cenm. The number of carpels may be mucii 

 reduced in Siblaldia, but is here indefinite. The 

 summit of the receptacle rises into a slender foot, 

 dilated into a swelling at the apex whore it bears 

 the carpels, each with a little eylinilrical stalk, a 

 nearly gynobasic style and an ovule with a single 

 coat, whose micropyle looks upwards and out- 

 wards. 



•• Ekdl., Gen., n. Q^QCi.— Siblaldia tetrandta 

 Bge., Ter:. Alt. Pjlanz., 25. 



