THE BEHAVIOR OF CERTAIN MICRO-ORGANISMS IN BRINE. 53 



the salt as it crystallizes out, gradually become rose pink. Larger volumes of brine, with 

 more or less clay and other matters in suspension, exhibit a deeper color, but a color no 

 deeper than that of the pure colonies on an agar-agar plate or a streaked tube. To this 

 I shall return later. 



DESCRIPTION. 



In addition to the animals described by others as inhabiting concentrated brines 

 (Artemia, Amoebae, etc.) there must obviously be a sufficient number of plants to furnish 

 them food. It was to answer my own question as to what these animals feed upon that 

 I first examined the waters at the salt works on the shore of the Bay of San Francisco. 

 The food is principally two species of unicellular green algae. According to Oltmanns's 

 classification of the green algae, Chlorophyceae, this order is divided into five sub-orders, 

 viz, Volvocales, Protococcales, Ulotrichales, Siphonocladiales, and Siphonales, of which 

 the lowest is the Volvocales. The Volvocales in turn are divided into families, of which 

 the lowest is the Polyblepharidaceae. To the genera, Polyblepharis and Pyramimonas, 

 recognized by Oltmanns as belonging to this family, Teodoresco and Fraulein Hamburger 

 would add Dunaliella, a new genus cut off from Chlamydomonas. Believing that I had 

 the organisms described by Teodoresco and Fraulein Hamburger, I sent a bottle of brine 

 with the plants in it to Teodoresco at Bucharest, and received in reply a letter stating that 

 he recognized in my material the two species described by him, namely, Dunaliella salina 

 and D. viridis (see figures la and lc, Plate 9). Unfortunately, only a part of the organisms 

 survived the long journey in sufficiently good condition to be determined, for the records 

 show that other unicellular green algae occur at certain seasons. I have no doubt that study 

 of these salterns continued throughout the year by a taxonomical algologist would yield 

 a harvest of new species really inspiring to him; but beyond believing that at certain 

 seasons a species of Carteria appeared, to represent the Chlamydomonadaceae, and at others 

 a curiously flanged form, presumably a species of Pyramimonas (see figure 16, Plate 9) 

 another of the Polyblepharidaceae according to Dill, 1 I did not feel able to attempt to go; 

 and I was more interested in the relation between the appearance and the behavior (modes 

 of reproduction, etc.) of these organisms and the varying concentrations of the solutions 

 in which they lived. 



In addition to these algae there are a great number of bacteria, which also aroused 

 my interest; but I made no attempt to isolate them, with the single exception of the red 

 chromogenic form already referred to in this paper, and also in previous annual reports. 2 

 Decay follows death in these brines, although they are concentrated enough to serve as 

 preservatives for organic substances originating in relation to fresh water or to ordinary 

 sea-water. It follows, therefore, that the usual putrefactive bacteria are not the ones 

 concerned, and that the breaking down of the bodies of dead Artemias and of the waste 

 of the algal vegetation of the salterns is brought about by a set of saprophytic bacteria 

 entirely different from those to which we are accustomed. The action of these bacteria 

 is putrefactive, if by putrefaction is meant decay accompanied by offensive odors, for 

 there are often distinctly unpleasant odors in the salterns; the brine itself may smell badly, 

 the salt produced may have a disagreeable odor, and in such materials as codfish strongly 

 impregnated with the crude, or even refined but unsterilized, salt from these works, the 

 odors of decay are more or less marked according to circumstances. By circumstances 

 I mean mainly the weather — the temperature and the humidity of the air. Fish "pre- 

 served" with such salt and kept dry will be comparatively odorless; it will be the more 

 nearly odorless the drier and colder it is ; but if in damp air it becomes moist, by the salt 



1 Dill, O. Die Gattung Chlamydomonas und ihre nachsten Verwandten. Jahrb. f. wiss. Bot., vol. xxvm, 1895. 



2 Year Book, Carnegie Institution of Washington, Annual Report of the Director of the Department of Botanical 



Research, vol. 11, p. 53, 1912; vol. 10, p. 51, 1911; vol. 9, p. 56, 1910. 



