02 Proceedings of the Royal Society of Victoria. 



has the cleavage marked at 50^. After a careful examination of 

 this section, I feel bound to conclude that the bedding and 

 cleavage have been confused, as the bedding is clearly seen 

 throughout the whole length of the cutting, and that the usual 

 high angle of cleavage is maintained. Cleavage is rarely well 

 sliown in the immediate neighbourhood of anticlines and synclines. 

 The rocks tend to become rubbly and frequently a system of close 

 set radial joints is developed. These joints are well displayed in 

 many of the x'ailway cuttings ; for instance, in a syncline 200 

 yards west of the Elphinstone tunnel. Mr. E. J. Dunn* regards 

 this structure as cleavage, and states moreover that the direction 

 of the dip of cleavage varies at Bendigo, l)ut that an easterly dip 

 is more common than a westerly one. 



There must of course, in such contorted beds as we are dealing 

 with, be places in which cleavage and bedding coincide, but I 

 have met only one instance of such. This is in the Barker's 

 Creek slate quarry, where the beds dip westerly at more than 

 85°. Mr. Reginald Murrayf says, when speaking of our silurian 

 rocks, that " stratitication and cleavage are generally identical, 

 but cleavage distinct from sti'atification is not uncommon." 

 Ulrich| states that the cleavage "frequently very nearly coincides 

 with the planes of stratification." As I have searched for grapto- 

 lites all over the district, the divergence of cleaAage from strati- 

 fication has been brought home to my mind very strongly. , When 

 the two differ much in direction, as when the beds dip east and 

 cleavage is strongly developed, a long time has frequently to be 

 spent iu search of indentifiable fossils, till by chance a specimen 

 is found the long axis of which accords with the stx'ike of the 

 rocks. 



Jointing is of course usual, and well developed, iu most of the 

 sandstones. Owing to the joints being close, large blocks of 

 stone are rarely obtainable, and frequently the sandstones are 

 rubbly. Occasionally, as shown at the east end of Lyttleton 

 Street, the joints are so well and evenly developed that the arch 

 appears to be built of masonry. 



Faults. — Strike-faults, as seen in the cuttings are very common, 



* hoc. cit., p. 14. t Geol. and Phys. Geog. Vic, p. 41. 



t Catalogue of Rock Specimens in Tech. Mus. Melb., 1875. Printed iu Parliamentary 

 Papers, and also issued separately). 



