346 Transactions. 



Fossils are very scarce in the Waipara greensands, the most common 

 being an obscure form from the lower group which has defied recognition. 

 They consist of calcareous tubes, | in. to 1 in. in diameter and a few inches 

 in length, the interior being filled with matrix. Von Haast (1871b) recorded 

 the presence of " some shells which appear to be allied to Radiolites,"' 

 and the specimens he collected are preserved in the Geological Survey col- 

 lections. They resemble the calcareous tubes collected b}^ me, but are 

 distinguished by the presence of nodal-like marks at intervals, giving the 

 specimens an external resemblance to an equisete stem. Dr. Marie Stopes, 

 who kindly examined the series of specimens, writes that they are certainlv 

 not Equisetinean or structures of any higher plant, and that Professor 

 Garwood, who also carefully examined them,' concluded that they were not 

 algal ; she showed them also to specialists working on lowly animals, but 

 none of them would claim them, and the consensus of opinion was that 

 they were inorganic. Von Haast (1871a) recorded also from the lower 

 group _■' Waldheimia leutmilaris and some pieces of a Pecten too small for 

 recognition," and from the upper group two small Pectens, Waldheimia 

 lenticularis and Scalaria hrowni (?). Park (1888) recorded a Waldheimia and 

 a Pecten. from the lower group. Unfortunately, none of the above fossils 

 are preserved in the Geological Survey collections. McKay (1877a) col- 

 lected bones of Cimoliosaurus australis in a detached mass of greensand near 

 the junction of Birch Hollow with the Waipara River, and in 1913 I 

 obtained part of a saurian jaw with teeth in a hard band near the top of 

 the upper group at the same locality. These two saurian occurrences serve 

 to unite the Waipara greensands with the saurian beds in the Piripauan. 

 There is every appearance of conformity, however, with the succeeding 

 group. 



Birch Hollow. — The sequence of the "' saurian beds " and Waipara 

 greensands in Birch Hollow is essentially similar to ttiat in the Waipara 

 River, but owing to the flatter dips, and the slipping of the sides of the 

 narrow gorge, the thickness of the beds cannot be easily estimated. The 

 creek is nearly choked below the Ostrea bed by the abundance of saurian 

 concretions coming from the grey sandy mudstones. Many of these show 

 saurian bones and a few are crowded with gasteropods, but are too hard 

 to break with an ordinary hammer. A good collection of saurian remains 

 could be made from this gorge if the difficulties of transport could be solved, 

 but they are very considerable, as the sides form sandy cliffs nearly 200 ft. 

 in height, while the bottom is choked for over a mile with fallen beech-trees 

 and large boulders. The greensand bed separating the grey, streaky, sandy, 

 concretionar)' mudstones below from the purple sulphur mudstones above 

 is about 6 ft. thick, and is characterized by an abundance of small quartz 

 pebbles of about ^ in. diameter. The purple micaceous mudstones are 

 well exposed in the main northerly tributary, which I did not explore, and 

 appear to be upwards of 200 ft. thick.. They do not appear here to bear 

 any saurian concretions, and I noticed only one small concretion, of 4 in. 

 diameter. The banded concretionary greensands do not appear to be more 

 than 50 ft. thick, while the succeeding upper greensands at the mouth of 

 the creek are perhaps thicker than in the Waipara River, and contain an 

 abundance of pyrite nodules up to 3 in. or 4 in. in diameter. They are 

 very dark, richly glauconitic, soft sandstones, with occasionally a tendency 

 to assume a shalv parting, and in places have a very strongly marked 

 sulphur efflorescence. From them I obtained a minute shark's tooth, con- 

 sidered by Mr. P. G. Morgan to be Odontaspis sp., and similar to 0. attenvata 

 (Davis). 



