THE VICTORIAN NATURALIST. 75 



A New Geological Map of Victoria. — The princi|)al feature 

 of interest to the field naturalist in the recently issued " Victorian 

 Settler's Guide," published by the Lands Department of Victoria, 

 is the new Geological Sketch Map of the State, accompanied 

 by an article on Victorian rocks and their resulting soils by Mr. 

 E. J. Dunn, F.G.S., Director of the Geological Survey of 

 Victoria. The map gives considerably more detail than the 

 previous one in Murray's " Geology and Physical Geography of 

 Victoria," published by the Mining Department in 1887. In the 

 present edition twelve colours are used in place of nine, and 

 consequently it has been possible to divide the areas of volcanic 

 rocks into newer and older, likewise the Silurian into Silurian 

 (upper) and Ordovician (lower). Many other changes in 

 determination of various areas have been made, and altogether 

 the map indicates a considerable advance in our knowledge of 

 the geology of the State. A quantity of other useful information 

 is included in the guide, together with illustrations and maps 

 showing water supply, temperature, rainfall, butter factories, and 

 finally the State, on the scale of 16 miles to the inch, classified 

 according to its productiveness. This map is particularly 

 attractive, being coloured to show at a glance, besides many 

 other interesting minor details, whether the land is adapted for 

 agriculture, grazing, fruit growing, or is reserved for forest and 

 timber-growing purposes. 



Fighting Ants. — Towards the end of October, 1904, I 

 witnessed an encounter between two species of ants, one of which 

 was probably identical with that mentioned by Mr. J. A. Hill in 

 his interesting paper on the subject in the June Naturalist, vol. 

 xxii., p. 35. There can be no doubt from the description that the 

 larger species, Formica purpurea, was the same ; it is known in 

 many districts as the " Meat Ant," from its well-known predilec- 

 tion for flesh of any kind. The smaller species, Crematogaster 

 Imviceps, has a black, heart-shaped abdomen, which it turns up 

 in a threatening manner when disturbed ; its nests are usually 

 placed in or under pieces of fallen dead timber. The courage of 

 both is of a high order, though Crematogaster is the more deter- 

 mined fighter. In this case the larger ants were the aggressors. 

 My attention was first drawn by seeing a constant stream of F. 

 purpurea,, in a state of great excitement, running swiftly along a 

 footpath ; many were returning to the nest laden with the dead 

 bodies of Crematogaster. Following the line of march for 20 

 yards I came to tlie battle-ground, and a remarkable scene it 

 was. The small ants had established their nests round about 

 the base of a tree from which young " suckers " had grown up, 

 and this tree and bush they were holding against the attacks of 

 their (to them) gigantic foes The small warriors were drawn up 

 in a dense black line, from i to 3 inches in depth, extending in 

 an irregular circle about 3 feet in diameter round the busli. The 



