400 BOTANICAL GAZETTE [MAY 
They are certainly not algae, but spores of pteridophytes, a group which 
constituted an important part of the paleozoic vascular flora, and which has 
always been regarded as responsible, to a large extent at least, for the ordinary 
coals. is conclusion sets aside the algal hypothesis of the origin of petro- 
leum and other substances, and refers such products to the waxy and resinous 
spores of pteridophytes, ‘laid down on the bottoms of the shallow lakes of the 
Coal Period. These lacustrine layers, either as cannels, bog-heads, or bitu- 
minous shales, according to the sporal composition and the admixture of earthy 
roleu 
either separately or combined, in the presence of permeable strata, have 
brought about the distillation of petroleum from such deposits.” —J. M. C. 
Alkaloids and algae.—Comere? finds that some alkaloids can be used by 
algae as the only source of nitrogen. The algae used were Ulothrix subtilis 
and Spirogyra crassa, and the alkaloids were morphine hydrogen chloride, 
atropine sulphate, cocaine hydrogen chloride, quinine hydrogen chloride, and 
strychnine sulphate. The alkaloids were added gradually as assimilated, so 
that the plants were never subjected to strong solutions. Ulothrix proved 
to be far more amenable to cultural conditions than Spirogyra. It can readily 
assimilate morphine and atropine, and less readily cocaine; Spirogyra showed 
less marked assimilation of these compounds. Quinine could not be assimi- 
lated by either, and strychnine was very toxic to both, even in great dilution. 
Some of the alkaloids, therefore, are not aplastic—W1Lt1aAM CROCKER. 
Response to light—DancEarp” finds that in three species of Chromatium 
studied (C. Okenii, C. vinosum, C. sp. ?) there is a marked accumulation in the 
longer rays of the spectrum as observed by ENcELMANN. In the infra-red 
there are two regions of accumulation; one in ray lengths 0.840-0.820 #, and 
the second at 0.800-0.790 4. In the visible spectrum there is a zone of 
accumulation between the B and C lines, and a second one extending to each 
side of the D line. A green bacterium that he recently described also responds 
to longer rays; it accumulates in a zone with ray lengths 0.770-0.670 ». 
Some other experiments, claimed to show the relatively great effectiveness 
of yes rays in assimilation and growth, add nothing of value to our knowledge. 
ILLIAM R. 
* CoMERE, JoserH, Du rdle des alcaloides dans la nutrition des algues. Bull. 
Soc. Bot. France 57: 277-280. IgIo. 
7? DANGEARD, P. A., Phototactisme, assimilation, phénoménes de croissance. 
Bull. Soc. Bot. France 57: >315-319. 1910 
