— loy — 
thesis by Carl Ernst Julius Lohmann^). From the work, entitled 
"Contribution to the Chemistry and Biology of Hepatica", we abstract 
the parts on essential oils which are of interest to us. 
From all the hepatica examined by the author [Fimbywia Blumeana, 
Pellia epiphylla, Metzgeria furcata, Fegatella conica, Marchantia polymorpha, 
Mastigobryum trilobatum^ Lunularia vulgaris^ Targionia hypophylla, Aneura 
palmata, Madotheca platyphylla) ^ essential oils could be obtained by 
steam distillation. The yields fluctuated between 0,0 1 and 0,9 ^/^ of 
the dry substance. The odour of the oils reminded of the respective 
mosses. In view of the small quantities — frequently it was a question 
of only a single drop, but very little could be ascertained about the 
chemical character. The author determined by analyses the ratio of 
carbon to hydrogen as 1,51 to 1,61, and from this he deduced the 
fact that the oils belonged to the terpene-series. The oil of Mastigo- 
bryum trilobatum which was examined most in detail (of this about 
8 gm. =o,9^/q were available), had at 16° the specific gravity 0,972, 
and deflected the plane of polarised light to the right. It boiled at 
270° to 285°. In the residue there remained a brown-coloured viscid 
liquid which solidified into colourless needle-shaped crystals. Dried 
between filtering paper, they melted at 78° to 85°. With acetic acid and 
concentrated sulphuric acid the oil gives a red colouration. In ethereal 
solution it absorbs bromine, but it does not yield a crystallised bromide. 
With regard to the usefulness of the essential oils, the author agrees 
with Detto'-^) that they form a protection against animals. 
Hydrocarbons. 
For the hydration of terpenes, Semmler^) had recommended the 
use of sodium and alcohol and had been able to accomplish thereby 
reductions in the case of hydrocarbons with so-called conjugated double- 
linkings. Semmler had further mentioned the possibility that the 
capacity for reduction of unsaturated phenol ethers is dependent upon 
the proximity of the aliphatic double-linking in the benzene-nucleus, 
and he arrived at the conclusion that these two contiguous double- 
linkings were capable of reacting like a conjugated system. This view 
is opposed by Klages^) who demurs to the equalisation of an aliph- 
atic double-linking and one of the three double-linkings of the ring 
on which the benzene character depends. From his earlier as well 
as his more recent work, Klages concludes that the reduction of 
the vinyl, or the propenyl side-chain, essentially depends upon the 
character of the radicles linked in the side -chain and also in the 
^) Thesis, Jena 1903. 
2) Report October 1903, 82. 
^) Berliner Berichte 36 (1903), 1033. — Report October 1903, 83. 
^) Berliner Berichte 36 (1903), 3584. 
