1835.] Miscellaneous. 119 



2Z. How long and in what manner can the impregnated ova of fishes be pre- 

 served, for transportation, without preventing vivification when the spawn is 

 returned to water. 



26. Further observations on the proposed metamorphosis of decapod Crus- 

 tacea, with reference to the views of Thompson and Rathke. 



27. Further observations on the situation of the sexual organs in male spi- 

 ders, and on their supposed connexion with the palpi. 



28. The use of the antennae in insects. Are they organs of hearing, of smell, 

 or of a peculiar sensation ? 



29. The function of the femoral pores in lizards, and the degree of import- 

 ance due to them, as offering characters for classification. 



Botany. 



30. An accurate account of the manner in which the woody fibre of plants ia 

 formed. 



31. An investigation of the comparative anatomy, of flowerless plants, with a 

 view to discover in them the analogy and origin of their organic structure. 



32. The cause of the various colours of plants. 



33. The nature of the fsecal excretions of cultivated plants, and of common 

 weeds ; the degree in which those excretions are poisonous to the plants that 

 yield them or to o triers ; the most ready means of decomposing such excretions by 

 manures or other means. 



Tides. (See Journal Asiatic Society, vol. IT. page 151.) 

 Falling stars. M. Quetelet's mode of observing and recording the charac- 

 teristic circumstances of these meteors is recommended to notice. " I take my 

 station out of doors, in a situation which commands a good view of the sky, with 

 a map of the heavens spread out before me. When a falling star appears, 

 I mark on the map the point of its commencement, the line of its 

 course among the nearest stars, and the point where it vanished. This is done by 

 an arrow-line. A number of reference is added, which connects it with a book- 

 register of the exact time, magnitude, duration, and other circumstances. Contem- 

 poraneous observations at distant stations are much desired. 



2. — Manilla Indigo, (so called.) 



There has lately appeared in the Calcutta market an article purporting to be 

 Indigo from Manilla. The packages containing it are to all appearance Chinese, 

 being covered with mats and tied round with split ratans like tea-boxes. A 

 sample of this having been sent me in August last, for comparison of quality 

 with other Indigo, I caused a portion to be incinerated, and found the ash highly 

 ferruginous, and weighing 52 per cent, of the whole, — 18 being the greatest per- 

 centage I had ever found, and that only in refuse Indigo. The specific gravity was 

 lvO. Some of the ash dissolved in muriatic acid afforded a copious precipitate 

 to Mur. Barytes, and to Prussiate of Potash. I therefore imagined that the Indigo 

 had been precipitated from the vat with a ferruginous alum, and proceeded no fur- 

 ther with its examination. 



Having been however recently favoured with another sample from Mr. C. K. 

 Robison, under a suspicion that the substance was not Indigobut Prussian Blue, 

 I submitted a portion to tests which at once proved the truth of this supposition. 

 By digestion in caustic alkali, hydrocyanic acid may be taken up while the oxyde of 

 iron remains behind ; on acidifying the solution and adding to it a drop or two of 

 sulphate of iron, the Prussian Blue is again formed. The readiest test, however, 

 is to place a small portion of the suspected matter on a hot coal or iron. If it 

 be indigo, a fine purple smoke instantly rises, and it takes fire. The Prussiate 

 gives off water, and at last burns feebly. It is also much heavier than indigo, but 

 its colour, in the cake, is a fine clear blue, rather of a coppery streak. 



It is reported that the article in question was manufactured in America, and 

 shipped to Fiance, where Indigo was selling at 14 francs. Being unsaleable, it 

 was re-shipped to America, whence it found its way to Canton, where it under- 

 went some change, and was brought to Calcutta, and remains to spread alarm 

 among our manufacturers of Indigo, at the prospect of a fair competition in the 

 blue market they have so long monopolized. — Ed. 



