BOTANY. 337 



states their price to be 190/. to 380?. per ton, and that in times of scar- 

 city the orcellas have sometimes fetched 1000/. per ton ; whilst he 

 remarks on the above-quoted note that he believes a similar statement 

 might be made with respect to many islands in the Atlantic and Pacific, 

 which probably abound in this vegetation, furnishing, like Ichaboe and 

 other sources of guano, a hitherto unsuspected field of profitable trade. 

 The great similarity of species in external form and appearance is a 

 favorable element of successful research, since, whether natives of the 

 Ancles, of North America, New Holland, Africa, Madagascar, or the 

 Himalayas, these tribes are similar if not identical with the European 

 species. Of tests, to distinguish between the dyeing and the valueless 

 lichens, Hellot's is the easiest and most certain, if not in every respect 

 the best. Having previously dried and pulverized the lichen under 

 examination, steep it in a weak solution of ammonia for several hours 

 in a warm place, a temperature of 130 Fahr. being that recommended, 

 stirring occasionally to expose fresh surfaces to the air, when, if the 

 plant be a dyeing lichen, the solution will gradually acquire a purple 

 red color, from the intensity and beauty of which, a comparative judg- 

 ment of the commercial value of the orchil may be estimated. Stale 

 urine may be substituted for the weak ammoniacal solution, should the 

 latter be wanting. By the mutual action of the atmospheric oxygen 

 and the ammonia, assisted by the heat and the moisture on the dyeing 

 principles of these lichens, existing in the plant in a colorless state, 

 new compounds are formed, in which the colorless dyeing principle is 

 transformed into the beautiful purple-reds characteristic of the dye- 

 lichens. 



VEGETABLE IVORY. 



Berthoed Seeman in his account of the voyage of the Herald, R. 

 N., Capt. Kellett, recently published, has the following notice of the 

 vegetable ivory nut of South America. 



In Darien, on the banks of the river Cupica, vast groves of vege- 

 table ivory, a species of the genus Phyteleplias, probably distinct from 

 that found on the Magdalena, were met with. The Darien kind is 

 always collected in separate groves, growing gregariously and unmin- 

 gled with other trees, or even herbs, the ground beneath these palms 

 (or rather screw-palms) being as bare as if it had been swept. The 

 flowers of both male and female trees are exceedingly odorous, emit- 

 ting a scent like that of almond-essence, and attracting swarms of bees. 

 The fruits are aggregated in heads, each plant bearing from six to 

 eight of these masses of drupes at one tune. On an average each 

 head contains eighty seeds, and when ripe weighs about twenty-five 

 pounds. No use is made of them, however, although they might be 

 turned to excellent account, and we call the attention of speculators to 

 this discovery as one of considerable commercial interest ; the more so, 

 since at present much attention is being directed towards the products 

 and resources of Darien. 



