736 Queries mid Answers. 



Of the Otaheitean Arrow-7-oot (Tacca pinnqtifida L.), ivhat Proportion 

 does the Fecula yielded bear to the Weight of Tubers from which it is derived? 

 and -what is the Relation of the Weight of Tubers to the superficial Quantity 

 of Soil producing thai Weight? — Your correspondent, Mr. Mathews of 

 Lima, has furnished (p. 585.) a most valuable communication on the 

 fecula afforded by the roots of the Tacca pinnatifida, and the mode by 

 which it is separated from them by the inhabitants of Otaheite. To this 

 information if he could furnish a statement of the proportion of fecula 

 obtainable from any given weight of the washed roots, and the probable 

 weight of roots obtainable as a crop from an acre or any other given 

 quantity of ground, he would confer an obligation on such of your readers 

 as reside in countries adapted to the cultivation of this esculent. Its in- 

 troduction into our West Indian Islands, by increasing the amount of 

 human food produced within them, would perhaps be attended with much 

 advantage to the inhabitants, both as a source of domestic supply and of 

 profitable exportation; and if any of your readers should possess a suf- 

 ficient share of philanthropy to furnish me (under a frank) with a few of 

 the seeds, it will afford me much pleasure to distribute them among my 

 correspondents in the West Indies, accompanied by any information re- 

 specting their culture, &c, which the donor may feel disposed to transmit 

 to me along with them. — Wm. Hamilton, M.D. Oxford Place, Plymouth, 

 Oct. 15. 1832. 



How can Plants of the Genus Citrus be prevented shedding their Leaves 

 and young Fruits? — I should be much gratified if any cultivators of the 

 genus Citrus would inform me of a method to prevent the plants shedding 

 their leaves and fruit on being removed from a green-house to another 

 situation. This last season I removed three large plants from a green- 

 house to a light airy room, of very similar temperature, and the door of 

 which was almost constantly kept open, as was that of the green-house. 

 Notwithstanding this parity in the condition of the plants, they lost many 

 of their leaves and all their small fruit. — I.J. Oct. 13. 1832. 



The Corolla of Calystegia sepium Brown closes in a different Manner from 

 that in which the Corolla of Ipomce s a purpurea Lamarck closes : is there any 

 Difference of Structure to account for this ? — In my garden, Calystegia 

 sepium and Ipomce v a purpurea are growing together, and are twining up 

 the same strings. I have watched them attentively in all their stages of 

 flowering, and have seen with surprise the different manner in which the 

 corollas close when they begin to fade. Those of Calystegia sepium close 

 together in longitudinal folds, while the edge of the corollas of Ipomoe v a 

 purpurea curls inwards upon the parts of fructification. Is there any dif- 

 ference in the structure of the corollas, to account for the difference in the 

 manner of their withering ? — John R. Rowe. Wimborne, Sept. 15. 1832. 



The fittest Soil for, and Management of, Auriculas in loiv Situations. — Sir, 

 I should feel grateful for plain directions as to soil and management 

 requisite for the Primula Auricula in low situations. In Vol. IV. p. 246. 

 you mention Mr. Gray's having written a judicious paper on this subject ; 

 but of his mode of treatment no mention is made. It is something of 

 this kind that I am in want of, as I have Hogg's Treatise on Florist's Flowers. 

 I am, Sir, yours. — R. W. 



On preserving Cape Heaths from Mildew. — I should feel greatly obliged 

 to any cultivator of that most beautiful and interesting genus .Erica, for an 

 explanation of the cause, and instructions for the prevention, of a sort of 

 mildew which sometimes attacks these plants in our green-houses and 

 frames. It frequently destroys a whole set of plants in a very short time. 

 I find no account of it in the last edition of Sweet's Rotanical Cultivator, 

 nor in M'Nab's Treatise on Cape Heaths. I have been informed that 

 suffering water to be poured over their tops will cause it ? I hope some 

 experienced cultivator will early advise me on this point. — R. W. 



