CAMBRIAN 243 



has discovered sponge spicules in an ancient dense limestone, intermixed with sub- 

 marine tuff from the Stranded Moraine in the east fork of the Ferrar Glacier. 

 The fossils noticed are several broken pieces of sponge spicules ; the fragments are 

 each in length about Uxo or three times the diameter of the spicule. In each case 

 the central canal is clearly preserved, and the silica remains in its original colloidal 

 form. Professor Skeats compares them with sponge spicules which he has found in 

 cherty rocks of the Heathcoatian series in Victoria, which is believed to be either 

 Lower Ordovician or Upper Cambrian. Dr. Hinde agrees with Professor Skeats in 

 referring these organisms to sponge spicules. 



In addition to limestones of Cambrian age there are certain rocks, termed by 

 Mawson arkose-greywacke, which may perhaps also be Cambrian, though it is 

 possible that they are of Beacon Sandstone age. Mawson states " by a study of the 

 marine derived specimens it is not possible to say how far the quartzites represent 

 the Beacon Sandstone, or to what extent they proceed from older formations." 

 Mawson suggests that the red colour of some of the limestone fragments, as well as 

 of the arkose, suggests that they may have been deposited under semi-arid, possibly 

 semi-glacial, conditions. Only one other formation is known to us in South Victoria 

 Land which mav be considered to belonof to the Cambrian formation. This is a 

 greenish-grey slate, numerous fragments of which were found lying upon the surface 

 of the Beardmore Glacier in the neighbourhood of the Cloudmaker. They had 

 obviously been blown on to the ice from slate rocks in situ from the hills farther 

 south. The slates are probably at least older Palaeozoic in age. 



DEVOMAN 



BEACON SANDSTONE (ix i>akt) 



The announcement was made by Mr. Griffith Taylor to the Royal Geographical 

 Society that the fossil fish plates discovered by F. Debenhara and himself at Granite 

 Harbour are considered by Dr. A. S. Woodward to be undoubtedly of Devonian 

 Age, obviously an extremely important discovery.* 



* Hence the lower part of tlie Beacon Sandstone will hereafter probably have to be classed as 

 Devonian. 



