662 SUMMAR? OF CURRENT RESEARCHES RELATING TO 



of the alga, and compares it with P. < lementi, its nearest ally. P. dementi 

 is however a terrestrial form, while I', marinus is a marine species. 



A. Paacher describes a new genus of Chrysornonadinae, which he 

 found growing in masses of Microspora and (Edogonium in a park at 

 Pranzensbad. It is very closely allied to the somewhat mysterious Pedi- 

 nella of Wyssotzky, both possessing remarkable tentacles. The author 

 describes the structure and life-history of this new alga, which he calls 

 { 'yrtophora pedicellate. He proposes to form a new family of the Chro- 

 mulinales, Cyrtophoraceae, to include Pedinella, GyrtopJwra, and Palati- 

 nella Lauterborn, all of which genera are characterized by the possession 

 of tentacles. 



Chlamydomonas Steinii * — P. Desroche describes in detail some 

 experiments he has made on the phototropism of the zoospores of Chla- 

 mydomonas Steinii Goros. He finds that light has no effect either in 

 hastening or retarding the movement of the zoospores. They have a 

 constant speed, which does not depend on the quantity of luminous 

 energy which they receive, but represents solely their own energy. Light 

 has no other action than to direct their movement. 



Coccogenous Cyanophycea.f — R. Chodat describes a new and re- 

 markable genus of Myxophyceaa from the park of Mon-Repos at Geneva. 

 It unites the characters of several genera of Cyanophyceas, being in fact 

 a mixture of Chamaasiphoneae, Oscillatoriaa, and Lyngbyaceaa. It develops 

 on a stone into a plate of chroococcoid cells of varying size, 1-3 /*. On 

 this plate arise short filaments of the type of Ghamsesiphon. Sometimes 

 the filaments reach a great length by stretching out in a regular manner 

 in their narrow sheath, but sometimes the cells twist spirally. The most 

 interesting stage is the detachment of conidia in chains. The isolated 

 cells become free by the rupture of the sheath or by escape from its 

 apex. The name given is Erustiella rufa. 



Oscillatoria rubescens.+ — H. Bachmann describes a remarkable 

 growth of this alga in the Rothsee near Lucerne. In the autumn of 

 1909 the lake was covered with a greenish powder composed of Gompho- 

 sphseria Naegeliana. Later on the ice formed, and that had a red tinge 

 from the Oscillatoria ; while in April 1910 Oscillatoria was growing in 

 such masses that it formed large flat cakes on the water. The smell 

 from the decaying alga was most unpleasant, and the fish suffered 

 considerably. On the other hand, Infusoria and Rotatoria flourished. 

 It is supposed that either the alga suddenly attained this extraordinary 

 multiplication, or that it was carried from the neighbouring Balder- 

 gersee by water-birds. The author compares the alga morphologically 

 with similar algaa from neighbouring Swiss lakes. 



Red Euglena.§ — A. D. Hardy writes an account of a red species 

 oi Euglena which he has found at Doncaster, Victoria, about eight miles 

 from Melbourne. He gives a full account of its habitat, form and 

 structure, as well as of the various experiments he made with it. As 



* Comptes Renclus Acad. Sci. Paris, clii. (1911) pp. 890-3. 

 t Bull. Soc. Bot. Geneve, iii. ser. 2 (1911) pp. 125-6. 

 J Naturwiss. Wochenschr., n.f. ix. (1910) pp. 602-4 (fig.). 

 § Victorian Naturalist, xxvii. (1911) pp. 215-20 (1 pi.). 



