CURRENT LITERATURE 
NOTES FOR SEUDENRTS 
The unarmored Peridiniales.—Excepting only the diatoms, no group of 
unicellular organisms is of such fundamental importance in the biology of the 
seas as the peridines, and there are few groups concerning which our knowledge 
is so unsatisfactory. This is ~~ true of the unarmored forms, 
which are not only apt to be r in collecting, but, if they survive the 
plankton net, are destroyed by ee preservatives used and usually remain recog- 
nizable for only a short time under the conditions speedily developed in a jar of 
sea water or on a microscopic slide. For these reasons all who have occasion 
to study the minute life of the ocean will heartily welcome the appearance of 
the splendid monograph by Kororp and Swezy.t About one-fifth of the 
text is devoted to topics of a general nature, the remainder to the detailed 
descriptions of genera and species. Among the topics discussed are the general 
and comparative morphology of the group, life cycles, physiology, including 
short but pregnant discussions of nutrition and luminescence, and finally 
The autho 
evolutionary development and_ distribution take marked 
exception to West’s statement that over 80 per cent of the peridines are 
“true vegetable organisms with a holophytic nutrition,” decl n the 
contrary that “the number actually containing chr ophores is relatively 
great abundance of some of the forms characterized by undoubted holophytic 
nutrition insures that the group will continue to be of as great interest to the 
botanist as to the zoologist. 
he authors regard the Peridiniales as a monophyletic group, derived 
from a cryptomonad ancestry, and describe a new genus, Protodinifer, which 
is One of the simplest known peridines. One line of development, starting 
near some such form, may have given rise to the Haplodinium, Exuviella, 
Prorocentrum series; another would lead to the simpler Gymnodiniaceae, from 
which coordinate lines of development lead on the one hand to the higher 
unarmored forms, culminating in such elaborately organized genera as Pouchetia 
and Erythropis, and on the other hand to the thecate forms, such as Ceratium. 
The systematic treatment includes descriptions of 223 species, distributed 
among 16 genera, of which Protodinifer, Gyrodinium, Torodinium, Pavillardia, 
Protopsis, Nematodinium, and Proterythopsis are new. Of these, Torodinium 
*Koror, C. A., and Swezy, Outve, The free-living unarmored de 
Memoirs Univ. Cal. 5: viii+-s62. pls. 12 (colored). figs. 388. Univ. Cal. Press 
Berkeley. 1921. 
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