MOLLUSCA. 131 



by Signior Bezio as a peculiar substance which he has de- 

 nominated Melaina. It is obtained by digesting the ink 

 with very dilute nitric acid, until it become yellowish, wash- 

 ing it well, and separating it by the filter ; it is then to be 

 frequently boiled in water, one of the washings to be a lit- 

 tle alkalized ; and, finally, with distilled water. The me- 

 laina is a tasteless, black powder, insoluble in alcohol, ether, 

 and water, whilst cold, but soluble in hot water ; the solu- 

 tion is black. Caustic alkalis form with it a solution even 

 in the cold, from which the mineral acids precipitate it un- 

 changed. It contains much azote. It dissolves and de- 

 composes sulphuric acid. It easily kindles in the flame of 

 a candle. It has been found to succeed as a pigment in 

 some respects, better than China ink. (Dub. Phil. Trans. 

 Nov. 1825.) 



The Cephalopoda are all inhabitants of the sea. They 

 are widely distributed, occurring in the arctic as well as the 

 equatorial seas. In the latter, however, they grow to the 

 largest size. It is reported, that in the Indian seas, boats 

 have been sunk by these animals affixing to them their long 

 arms, and that they are dreaded by divers. 



The two Linnaean genera, Nautilus and Sepia, compre- 

 hend all the animals which are at present considered as be- 

 longing to this class. 



ORDER I. NAUTILACEA. 



Furnished with a multilocular shell. 



This order is involved in the greatest obscurity. None 

 of the recent species have been subjected to an accurate 

 examination, so that their connection with the order Sepia- 

 cea may still be considered doubtful. Enough is known of 



