350 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Anatomy of Crustaceous Lichens.* — Eugen Lang contributes a 

 series of studies on the nature of the seemingly insignificant thallus 

 growth of some Lichens. Sarcogyne simplex, which grows on granite, 

 has been repeatedly described as almost or entirely wanting in thallus. 

 The specimen examined by Lang grew on dolomite, and nothing was 

 visible except the fruits, but after decalcifying the substratum a quite 

 substantial endolithic thallus was laid bare ; cortex, gonidial layer and 

 hyphas, which, in the lower parts of the stone, contain oil, and, mixed 

 with them, abundant spheroid cells. A specimen that grew on silicate 

 of lime showed no spheroid cells, but bundles of " oil " hyphre with 

 rather deficient oil-contents were present. The presence of " oil " in 

 the hyphas depends on the presence of carbonates in the substratum. 

 An examination of S. pruinosa yielded the same results : an abundant 

 thallus imbedded in the stone, and, after decalcification, the " oil " hyphaa 

 and spheroid cells were found in the deepest rhizoid layers. In both 

 these species he found the gonidial layer thinner when the lichen had 

 penetrated deeply into the stone. The growth of S. latericola was 

 entirely superficial, the gonidial layer was well developed, and no 

 trace was found either of " oil " hyphae or of spheroid cells. Several 

 other crustaceous lichens examined afforded the same results, proving the 

 influence of the substratum on the development of the gonidia and of 

 the specialised hyphae. Thus a different habitat entirely altered the 

 characters of the thallus. The writer notes the presence of fungi and 

 of their tendency to invade the lichen fruits, where there is evidently 

 more abundant nourishment to be had. 



Schizophyta. 

 Schizomycetes. 



Production of Acetylmethylcarbinol by Bacteria of the Bacillus 

 mesentericus G-roup.f — H. Desmots grew Bacillus mesentericus vulgatus, 

 B.fuscus, B.flavus, B. niger and B. ruber in media containing 2 p.c. of 

 peptone and of calcium carbonate, and with an addition of glycerin, man- 

 nite, glucose, dextrin or inulin, etc. The action is slow, but the sugar dis- 

 appears altogether. The formation of acetic and valerianic acids can be 

 demonstrated, and also of ethylic alcohol in small quantities. The 

 distillate has besides special properties : it reduces Fehling's solution 

 in the cold ; it rotates the plane of polarised light to the left ; it does 

 not restore the colour of fuchsin treated with bisulphite ; iodoform 

 is not formed if it is treated with iodo-potassic-iodide solution and am- 

 monia ; it is not precipitated by mercuric sulphate with heat. With 

 phenylhydrazine, crystals of osazone are formed, having a melting point 

 of 243° C. If this osazone is treated with oxidising agents, e.g. potas- 

 sium bichromate and acetic acid, long needle-shaped crystals are obtained 

 soluble in alcohol and ether, and having a melting point of 151° C. 

 These can be reconverted into osazone by the addition of phenyl- 

 hydrazine. The substance responsible for these reactions is acetyl- 



* Beit. Wiss. Bot., v. (1903) pp. 162-88 (13 figs). 

 t Comptes Kendus, cxxxviii. (1901) pp. 581-3. 



