122 SOME POISONOUS PLANTS IN N.O. SOLANACE^, iv., 



In Czapek's text-book — Biochemie der Pflanzen, p. 311— the 

 statement occurs that '■^Duhoisia Hopwoodii contains 1'1% of an 

 alkaloid, earlier known as piturine, which is identical with 

 hyoscyamine." And again, in Wehnier's text-book— Die Pflan- 

 zenstoffe, p. 695, the same erroneous statement is found. There 

 is no doubt that the name "duboisine" has been used for the 

 alkaloid of both plants. 



ix. About this time, Ladenburg was investigating the con- 

 stitution of the atropine group of alkaloids, and their i-elation 

 to one another. After reading the account of Gerrard's work, 

 he concluded that a more accurate chemical investigation was 

 necessary to decide the true nature of duboisine. 8ince only 

 two strongly midriatic alkaloids were known to occur naturally 

 — atropine and hyoscyamine,— Ladenburg set out to determine 

 whether duboisine was identical with one of these, or a new 

 tropeine alkaloid. This was all the more interesting as "datu- 

 rine," the alkaloid in Datura stramonium, had already been 

 shown to be atropine, by Planta, but was subsequently proved 

 by Ladenburg (34) himself to be identical with its isomer hyo- 

 scyamine. Ladenburg received from Merck, in 1880, a few 

 grams of duboisia sulphate in the form of a resinous residue. 

 Bv carefully purifying the gold salt, he finally obtained the very 

 characteristic crystals of gold hyoscyamine, m.p. 159°C.(33). 



Shortly after this, in 1880, Gerrard (36) announced to the 

 Pharmaceutical Society of London that he had succeeded in pre- 

 paring crystallised duboisine. This he obtained in two different 

 forms by a certain solvent (which he does not mention), and he 

 was unable to say whether these were of the same or different 

 constitution. 



In 1882, Gibson (37) studied the action of Duboisia on the 

 circulation, and his results showed the typical action of the 

 atropine group. 



Professor Harnack(39), the pharmacologist, subsequently chal- 

 lenged Ladenburg's statement that duboisine and hyoscyamine 

 are identical, and affirmed that the former was much stronger. 

 Ladenburg (40) was accordingly induced to return to the subject, 

 and, in 1 887, having obtained a few grams of the commercial 



