Flora of Australia. 20T 



July 2(j, 1918 

 Aiiyust 16, 1918 

 September 21, 1918 - 

 October 10, 1918 

 October 18, 1918 

 October 30, 1918 

 November 7, 1918 

 November 26, 1918 

 December 3, 1918 

 December 14, 1918 

 December 26, 1918 

 January 17, 1919 

 January 30, 1919 

 February 20, 1919 

 March 13, 1919 

 March 28, 1919 

 April 25, 1919 

 May 21, 1919 

 August 1 1919 



Throughout the autuiun and winter there was no evidence of any 

 expansion or contraction with changes of temperature within sl 

 range of 45°F., (34'F.-79°F.), the static measurement being 6 ft. 

 iOj-f in. On several occasions after rain had fallen and saturated 

 the bark, corrected readings of 6.10 ^^were given (May 23rd, June 

 2nd, June 15th, June 3€th, etc.), but between these times the mea- 

 surement reverted to 6 ft. 10_5_ in. It would be of interest to< 

 know in detail the method of standardization adopted by Trow- 

 bridge and Weil, and also what precautions were taken to dis- 

 tinguish between variations' of girth due to moisture and those- 

 supposed to be due to temperature. A variation of ^V in. in 6 ft. 

 lOy^ in. is approximately 0.07%, and if it were due to tempera- 

 ture, with a range of 45°F., it would represent 0.0017% per 1°F., 

 which would in any case be negligable in dealing with a material 

 like the trunk of tree. The view put forward by Trowbridge and 

 Weil that frost cracks are due to the pronounced contraction of the- 

 diameter of the tree and not to the expansion of frozen water merits 

 further investigation. 



Vkrbascum Blattakia, L. Spurious or Twiggy Mullein. 

 (Scrophulariaceae). 



In J. M. Black's Naturalised Flora of South Australia Ver- 



In J. M. Black's Naturalised Floi-a of South Australia, Ver- 



ralised aliens in South Australia, whereas in Victoria the only two- 



