Vol. XXVII. 



igii 



] Hardy, A Red Euglena. 215 



ON THE OCCURRENCE OF A RED EUGLENA NEAR 



MELBOURNE. 



By a. D. Hardy, F.L.S., F.R.M.S. 



{Read before the Field Naturalists' Club of Victoria, i^th Feb., 191 1.) 



In the summer of 1904 I received, through the courtesy of 

 Mr. F. G. A. Barnard, a small phial of brick-red fluid con- 

 taining " pond scum " from Doncaster, Victoria, and which he 

 suggested might be a form of Alga. The red matter, which 

 had been well shaken in transit, soon precipitated and was 

 lifeless, the force of offensively-smelling gas being sufficient to 

 blow the partially loosened cork out of the phial. Though 

 decomposition had made rapid progress, the nature of the 

 material was still discernible as composed of spherical cysts of 

 brick-red granular substance, the individual cells, which were 

 without integument, differing from each other only in size, 

 and that, in the majority of cases, only slightly. More 

 than a month passed before I obtained from the same source 

 a further supply, and this came to hand in a non-fluid state, 

 with the odour, colour, and plasticity of the anchovy paste 

 of commerce. This soiled the fingers with a smear as of greasy 

 clay, not removed by means of cold water only, but yielding 

 easily to alcohol, benzine, methylated spirits, and the like. 



No opportunity offered of prosecuting the inquiry further 

 at that time. Next summer I visited the locality on receipt of 

 a report from Mrs. Holden that the '' red scum " had appeared ; 

 and, after microscopical examination of the living organism, 

 found that not only was it a Euglena, but that in many respects 

 it differed from E. viridis, Ehrenb., the only form with which 

 I had any acquaintance. On reference to available literature 

 (a list of which is appended), and after some years of observa- 

 tion in the field, and further microscopical examination, it 

 seems to me that it may be necessary to constitute a new 

 species ; and for this I provisionally propose the name which 

 is henceforth used in this paper — viz., rubra. 



Doncaster is a portion of undulating country of Upper 

 Silurian formation, about 8 miles from Melbourne. To a 

 large extent it has been cultivated by orchardists, whose 

 water supply for stock, &c., is obtained from shallow artificial 

 catchments — excavations and dams — that are filled by direct 

 rainfall, surface drainage, and percolation. The water in 

 these holes is generally of a creamy or yellowish colour, due 

 to the soil, which, judging by the presence of quartz veins of 

 considerable length, is derived from rock decomposed in situ. 

 In late spring, during summer, and in early autumn a scum of 

 Euglena viridis frequently forms on these waters, and persists 

 through the calm, warm weather, but disappears with a faU 



