19 



Upper Bed — 13 (18 per cent.) tropical; 25 (35 per cent.) warm 

 temperate and tropical; 2 (3 per cent.) temperate ; 31 (43 

 per cent.) cosmopolitan. 



In their geological range; the Lower Bed contains six species 

 which date from Pahieozoic times, tive Trias, eight Lias, four 

 Jurassic, 18 Cretaceous, 68 Tertiary, five Quaternary, whilst 37 

 have not been previously noted in a fossil condition, and three 

 others only in Australian geology. 



In the Upper Bed two have a Paheozoic record, three Trias, 

 five Lias, three Jurassic, eight Cretaceous, 27 Tertiary, and 14 

 not previously observed as fossil forms. 



The occurrence of JSfu^nmulites variolaria in very great num- 

 bers in the Lower Bed is of special interest as showing uniformity 

 of palaeontological features between the Older Tertiaries of Aus- 

 tralia and rocks of a like age in Europe. The resemblance in 

 this respect is still further shown by the occurrence of large 

 examples of Ojjercnlina and other types which are commonly 

 iound associated with Nimiimdites in the Eocene Beds of the 

 Northern Hemisphere, and which are also conspicuous species 

 from Muddy Creek. 



In the material gathered by the " Challenger" expedition, the 

 Australasian region supplied a high proportion of the new species 

 obtained in this department of marine zoology. It Avas therefore 

 to be expected that the later geological formations of Australia 

 would show more or less resemblance to the dredgings in the 

 adjacent waters, and give geological examples of some of the new 

 species found in a recent condition. Including the new forms 

 ■described in this paper, 50 species occur in the list which are now 

 recognised for the lirst time as fossils. The general resem- 

 blance, which the Muddy Creek Foraminifera bear to the recent 

 species now inhabiting the northern and north-eastern shores of 

 tropical Australia, is very striking, and would appear to indicate 

 that in early Tertiary times either the tropical currents of 

 the ocean bore more directly on the southern shores of the conti- 

 nent, or that the zone of tropical heat reached nearer to the Pole 

 in the Southern Hemisjohere, as it appears to have done in the 

 JN'orthern, at the beginning of the Tertiary period. 



