GLANDULiE HUMULI. 555 



provided with the stalk is built up of tabular polyhcdric cells, wliilst 

 the upper hemisphere shows a continuous delicate membrane. Tliis 

 part therefore easily collapses, and thus exhibits a variety of form, the 

 greater also as the grains turn pole or equator to the observer.' 



The hop gland is filled with a thick, dark brown or yellowish liquid, 

 which in the drug is contracted into one mass occupying the centre of 

 the gland. It may be expelled in minute drops when the wall is made 

 to burst by warming the grain in glycerin. The colouring matter, to 

 which the wall owes its fine yellow colour, adheres more obstinately to 

 the thinner hemisphere, and is more easily extracted from the thicker 

 part by means of ether. 



Chemical Composition— The odour of lupulinic grains resides in 

 the essential oil, described in the previous article. The bitter principle 

 formerly called LujmUn or Lujndite was first isolated by Lermer (18G3) 

 who called it the bitter acid of hops (Hopfenhittersdure). _ It crystallizes 

 in large brittle rhombic prisms, and possesses in a high degree the 

 peculiar bitter taste of beer, in which however it can be present only in 

 very small proportion, it being nearly insoluble in water, though easily 

 dissolved by many other liquids. The composition of this_ acid, 

 C'W'O', appears to approximate it to absinthlin ; it is contained in the 

 glands in but small proportion. Still smaller is the amount of anotlier 

 crystallizable constituent, regarded by Lermer as an alkaloid. 



The main contents of the hop gland consist of wax {Myncylic 

 palmitate, according to Lermer), and resins, one of which is crystalline 



and unites with bases, , i • • i 



A good specimen of German lupulin, dried over sulphuric acid, 

 yielded us 73 per cent, of ash. The same drug exhausted by boiiing 

 ether, afforded 7G-8 per cent, of an extremely aromatic extract, wlncn 

 on exposure to the steam bath for a week, lost 303 per cent this 

 loss corresponding to the volatile oil and acids. The residual V^^^^l 

 soluble in glacial acetic acid and could therefore contain but very little 

 fatty matter. 



Uses-The drug has the properties of hops, but with less of 

 astringency. It is not often prescribed. 



Adulteration-Lupulin is apt to contain sand, ^^^^''l^''^^^^^^ 

 often leaves a large amount of ash. Other extraneous "^^"ei s .^ hi^h 

 are not unfrequeni may be easily recognized 1^ in cans of a lens 

 the essential oil in lupulin is soon resinihed, the latter snou v 



ferred fresh, and should be kept excluded from the an. 



' For a full account of the formation of be found "j ^ '^^j^ ^f ^^^^ 

 the glands, see Trecul, Annales cles Science, Lnpuhn, Montpellicr, 

 ^■nt. , Bot. , i. { 1 854) 299. Au abstract may 



