The Geology of the Lower Leigh Valley. 59 



they are not entirely so. Being a previously unexplored bed, 

 the majority of the new species recorded are, as might be expected, 

 from the amphitheatre marls ; in addition, these yield some 

 which, so far, have not occurred in our gatherings at the Bluft', 

 though they are known from more distant eocene deposits, as 

 Belmont, Curlewis, Birregurra, Spring Creek, etc. We have 

 thought it advisable to indicate the species which are special to 

 either of the two sets of beds mentioned. This information is 

 supplied more for the sake of future reference than for any 

 immediate use we propose to make of it. 



On the Bull Island section the fossils occur either loose on the 

 surface or slightly adherent to the marly matrix. Many of the 

 smaller species were obtained by sifting and washing the finer 

 and more calcareous material. 



Speaking of this and similar beds near at hand, Mr. Wilkinson, 

 who surveyed the area many yea:rs ago, says : " These clays 

 abound in well-preserved fossils. The surface of the out-cropping 

 beds often glitters with the white shells which have been exposed 

 by atmospheric action." When first seen by us this description 

 was still correct. Fossils have now, however, become very 

 scarce ; and since none can be got by digging, future collectors 

 must wait for a fresh crop to weather out. 



There are occasional bands of limestone in the marls them- 

 .selves, but above them the strata are composed of the former 

 rock only, arranged in a series of horizontal shelves, which show 

 for a long distance on the river banks. The limestone is a hard, 

 solid rock, and contains very few recognisable fossils, but these 

 few are also common in the clays. It took an hour's searching 

 to obtain the following : — 



Ostrea hyotis 1 Lovenia forbesii 



Waldheimia garibaldiana Lepralia edax 

 Waldheimia sp. Salenaria sp. 



and some indeterminable fragments. 



Though the marls and limestones are lithologically so different, 

 we yet regard them as palseontologically inseparable. We are 

 led to take this view, not so much from a comparison of the few 

 fossils collected in the upper strata with the rich fauna of the 

 lower as from observations made at the next section (No. IX.), 

 about a mile down the river and close to the southern boundary 



