74 USEFUL PLANTS OP GUAM. 



(ridlandhia crista has gv-A,y polished round seeds of stony hard- 

 ness, about the size of small marbles. "When shaken, these seeds, or 

 "nicker-nuts," giv^e forth a rattling sound, owing to the fact that the 

 kernel, consisting of two closely oppressed cotyledons, fits loosely in 

 the shell, leaving a large air space, which gives buoyancy to the seeds. 

 (PI. XV,' figs. 5, 6, 7.) 



The seeds of Lens pliaseoloides (PI. XV, figs. 2, 3, 4) do not rattle 

 when shaken. Their kernels fill the shell completely, but inclosed 

 Itstween the two large cotyledons composing the kernel there is a 

 large air space when the seeds are quite mature and drj-. They are 

 very light and float like bubbles on the surface of the sea. The seeds 

 of Stizolobium are easily distinguished from those of Lens by their 

 prominent raphe. Those of Lens have no raphe and are inclosed in 

 an enormous woody, saber-shaped pod (PI. LVl), consisting of many 

 distinct joints, with a strong wood}' suture surrounding the whole 

 legume. This suture is persistent and forms a sort of frame from 

 which the inclosed joints maj' be removed separately. Each joint (PL 

 XV, fig. 1) is in the form of a closed cell in which the bean fits looselj' 

 and rattles about when shaken. This plant owes its verj'^ wide distribu- 

 tion to the buoj'ancy of its seed and its habit of growing near the sea. 

 Great numbers of the seeds are thrown up each year by the Gulf 

 Stream on the Azores, but the plant has not succeeded in establishing 

 itself on those islands. Seeds collected there b}' Darwin were sent by 

 him to Sir Joseph Hooker. They were planted at Kew and many of 

 them germinated and grew to be fine plants, "showing that their 

 immersion during a voyage of nearly 3,000 miles had not affected their 

 vitality." * 



MoRiNDA ciTRiFOLiA. — This plant (PI. XVI), called "ladda," or 

 " lada," by the natives of Guam, has seeds of unusual interest. Their 

 buoyancy is insured by a distinct air cell. They are frequently found 

 in the drift of tropical shores, and experiments have been made which 

 demonstrate the great length of time they will float in salt water." 



the rocks about Jamaica, and is carried by the Winds and Current (which for the 

 most part go impetuously the same way) towards the coast of Florida, and thence 

 into the Northern Am. Ocean, whereas I mention p. 4. of my Oatal. it lyes very 

 thicli on the Surface of the Sea: But how they should come the rest of their Voyage 

 I cannot tell, unless it be thought reasonable, that as Ships when they go South 

 expect a trade Easterly Wind, so when they come North, they expect and generally 

 find a Westerly Wind for at least two parts of three of the Year, so that the Beans 

 being brought North by the Current from the Gulph of Florida, are put into these 

 Westerly Winds way, and may be supposed by this means at last to arrive in Scot- 

 land. Sloane, An Account of Four sorts of strange Beans, etc." Philosophical Trans- 

 actions, vol. 19, pp. 299, 300, 1696. 



6.1. D. Hooker, Insular Floras, Gardeners' ('lironicle, 1867, pp. 27, 51. 



«See Schimper, Die indo-malayische Strandflora, p. 165, pi. vu, fig. 26, b and c, 

 1891; also Guppy, The Dispersal of Plants, etc., Trans. Victoria Institute, vol. 27, p. 

 267, 1890. 



