38 The South Australian Naturalist. 



ship of Mr. E. Savage. The \mvty started at the freshwater 

 lake ill the 'Merusaleni" enclosure, and proceeded along the 

 drains near the \'iaduot. Owing to the dr}- weather, few speci- 

 mens of pond life were secured. The party then adjourned to 

 Mr. Savage's residence, where his aquaria were set out for 

 inspection, and Mr. Savage si)oke on the various aquatic plants, 

 freshwater tish, and pond life shown in the various jars. The 

 water hyaeinth in full bloom, various forms of Lemna, Vallis- 

 neria, and Chara Avere on view. The latter plant forms a living 

 coating on its stems which persists after the death of the plant, 

 and has in some instances accumulated in such quantities as to 

 form a limestone rock. ]\Ir. Savage showed various forms of 

 freshwater fish, wliich flourish in the jars, the oxygen being 

 sup})lied by the action of the aijuatic plants in the water. 

 Through the kindness of Mr. and Mrs. Savage a delightful and 

 most instructive afternoon was spent. 



Excursion on the Torrens Lake, March 11, 1922. — A trip on 



the Torrens Lake was undertaken by the Field Naturalists on 

 Saturday afternoon, March 11, under the leadership of Messrs. 

 B. Beck and H. Hale, to study the aquatic plants and animals. 

 Before going on the lake, Mr. A. J. Morison pointed out to the 

 members an old gum tree behind Webb's boatshed, which was 

 one of the very few remaining trees of the original forest. The 

 river weed known as Potamogeton (Gr. "potamos," a river; 

 "geiton, " near) belongs to the order of plants "belonging to 

 rivers" (Fluviales) ; this plant was found growing in abund- 

 ance on the lake, and is so thick now that parts of the lake are 

 covered with it. It is most un])leasant, if not dangerous, for 

 inexperienced oarsmen to get into, and certainly it is fatal for 

 swimmers to become entangled in it. The plant has its roots 

 in the mud, and grows long and numerous stems, which reach 

 the surface of the water. The several kinds of water fowl were 

 busy among the growt'h, feeding or resting. Intermingled with 

 this plant was another one with much more slender stems; in 

 fact, the stems of the S])irogyra were decidedly threadlike. 

 They were very green, and appeared to be slimy. The roots 

 were also growing in the mud, but the stems were supported 

 by the Potamogeton, which is of a much more robust growth. 

 This plant is frequently used to demonstrate the phenomenon 

 of the circulation of protoplasm in the cells. The native bulrush 

 (Typha angustifolia) grows very profusely along the banks of 

 the lake, and is known by its long flat leaves and slender brown 

 spike of flowers. This plant is only semi-aquatic, growing on 



