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Litter fall on two catchments, one with an almost continuous canopy of Eucalyptus spp., the other with a discontinuous eucalypt canopy was measured for 29 4-week periods. Annual litter accretion(2.5-3.7 t ha−1) was low by world standards, but similar to other Australian dry sclerophyll forests. Between 33 and 54% of the total litter fall occurred during summer, and only 6-13% in winter. Leaf was the major component of litter fall and usually contributed more than 50% of the total. Variability between the 4-weekly litter falls was high, but coefficients of variation for the total annual fall were low (

§1. Since the former paper on this subject was read, Prof. Cantor has published the second volume of his history of Mathematics. This has necessitated various additions to the paper, which can perhaps be best given as an appendix.On page 413 Prof. Cantor says that the construction of Dürer's pentagon is found in a book called Geometria deutsch, which was lately discovered in the town library at Nürnberg, and gives 1487 as the upper limit to its date. The construction is said to be “mitunverrücktem Zirckel,” the same expression that Schwenter applies to Dürer's solution.

Let ABC be the triangle, X, Y, Z the feet of the altitudes, H the orthocentre, A′,B′,C′ the mid points of the sides.Let ZY meet A′B′ in D, A′C′ in D′, B′C′ in R:ZX meet B′C′ in E, A′B′ in E′, A′C′ in S:XY meet C′A′ in F, B′C′ in F′, A′B′ in T.

The problem “to inflect a straight line between two sides of a triangle so that the intercepted portion is equal to the segments cut off” has been discussed in the third volume of the Proceedings.If we discuss the same analytically; taking CB and CA as axes of x and y (Fig. 1) and calling each segment k, the equation of the line considered is

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It can be shown by means of relative motion that if two bodies A and B move with velocities u and v in the same straight line, and a third body C move with velocity u + v also in the same straight line, the space passed over by C is equal to the sum of the spaces passed over by A and by B in the same time.

The perpendicular from A on BC = AB·AC/2R, which is constant.