^^is'] Hardy, Algcs of the Zoological Gardens, Melbourne. 89 



SOME ALG^ OF THE ZOOLOGICAL GARDENS, 

 MELBOURNE. 

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

 {Read before the Field Naturalists' Club of Victoria, 16th June, 191 3.) 

 This is one of a number of disconnected papers which had 

 been in preparation for some time, but suspended in anticipa- 

 tion of other botanical work of official and economic value. 

 In examining various bodies of water in connection with the 

 water supply of the Melbourne and Metropolitan Board of Works, 

 I had occasion — especially in searching for the cause of the 

 outbreak of salmon disease in the trout ponds of Studley Park 

 — to examine the Zoological Gardens' fish ponds, and advantage 

 was taken of the occasion to collect samples (at the invitation 

 of the Director, Mr. D. Le Souef, C.M.Z.S.) from other pools. 



The garden pools are all filled from the same source" — viz., the 

 city supply from the Yan Yean reservoir, supplemented by 

 water from the watershed of the Maroondah River direct from 

 the mountain weirs, the former supply being rich and the latter 

 poor in algal contents. But with this and other conditions 

 affecting them all aUke, the alga-flora of the respective pools 

 varies considerably in quantity, and I have found no species 

 paramount in all at one time. The pools are all shallow, with 

 no conspicuous benthos. They have almost similar environ- 

 ment, the larger bodies of water being almost continually 

 disturbed by captive aquatic birds. The pools may be thus 

 identified: — "Flamingo Pool," "Crane Pool," "Seagull 

 Pool." The first two of these are within stone-throw of each 

 other, and the third not far removed. 



Collections were made in igio, and occasionally since, 

 principally from the Flamingo Pool, which has attracted the 

 attention of many visitors, who have commented on the 

 singular appearance of the white-plumaged, pink-legged birds 

 standing or wading in green water. This pool is about 100 feet 

 long by 60 feet broad, with an average depth of two feet, and 

 is bordered with a retaining wall of rough rockwork at the 

 edge of the abutting grass lawns and shrubbery. Some 

 spreading oaks near by and some palms give occasional shade. 

 The collections were made chiefly during the warm season, and 

 incidentally while I was engaged on other business. Although 

 nothing in the nature of a systematic inquiry, or even an 

 exhaustive single survey, was attempted, the results with 

 regard to several points are interesting. 



Throughout nine months of the year, the water of the Flamingo 

 Pool is grass-green, the remaining three months being the 

 winter season, during which the colour diminishes, though not 

 to the vanishing point. During the warm season, cold snaps 



