210 



We did not observe any signs of disturbance in the strata, and 

 the forces which have raised them from the bed of the sea must 

 have operated very gradually. The tertiary strata of Australia 

 have, as a rule, a very small inclination, and many are horizontal. 

 There are exceptions, as at Longford, near Sale, where an Eocene 

 limestone, full of fossils, is inclined at a high angle. 



According to aneroid measurements, the highest cliff in the 

 Spring Creek strata is 220 feet above sea level. This is in Half 

 Moon Bay, and is probably the summit of the hemi-dome. For 

 about half the distance up, the usual fossils show, chiefly in bands, 

 where they are very thick; Fectunculus laticGstatus, Chione 

 Pritchardi, Carditn 'polynenia and a few other strong bivalves 

 especially weathering out. Their predominance here has given 

 rise to the erroneous theory, previously alluded to, that there is 

 a separate zone of bivalves above, and another of univalves 

 beneath. That this is not the case we proved by examining 

 these bands where the dip brought them within reach, as 

 univalves and other fossils supposed to be peculiar to the lower 

 zone were plentifully mixed with the bivalves. 



In the underlying softer strata the whole series was also repre- 

 sented — univalves, bivalves, brachiopods, polyzoa, echinoderms 

 and corals. The remaining half of the cliff consists of red and 

 yellowish sandy clays, with bands of hard rock. Owing to a land- 

 slip close at hand the topmost portion of these clays are acces- 

 sible. At lirst sight they appear unfossiliferous, but on a closer 

 examination fragments of shells, with occasionally a whole 

 specimen, can be found scattered very sparingly among them In 

 a two-hours' search the following were collected, chiefly on the 

 surface of the reddish strata: — (whole shells) Entalis Mantelli, 

 Cardita delicatula, Lhnopsis Belcheri, Pp.cten Foidcheri ; (frag- 

 ments) Voluta s;y., Turritella sp., Cytherea or Chione sp., 

 Cardita j)olynema (?). Our attention was first drawn to the 

 probably fossiliferous character of these clays by information 

 obligingly furnished by Mr. Mulder, that he had found fossils in 

 some clays about half-way up a steep bank thirty yards north of 

 Bird Rock, and which he supjDosed had fallen from above. The 

 following fossils were found on the spot indicated by Mr. Mulder: 

 — Murex n. sp., Peristernia lintea, (?) Voluta sp., AnciUaria 

 hehercB, A. ligata, Pleurotoma sp., T'urritella Murrayana, Entalis 

 Mantelli, E. suhjissura, Limopsis Belchei'i, Pecten Foidcheri. 



In the lower of the two subdi\isions of the cliff section the 

 sediments consist mainly of soft, brown, calcareous sandstones, 

 which not infrequently pass into hard rock. At the base of the 

 cliff they have a dark-bluish color, which changes to a reddish- 

 ])rown higher up, the first band of bivalves forming roughly a 

 dividing line. The blue sands occur only below high-tide mark, 



