March, 1007.] THE VICTORIAN NATURALIST. I99. 



resemble the pearly nautilus shell, but it is much more 

 ornate outside, and, instead of having the smooth, regular 

 partitions of the nautilus, it is divided up by partitions 

 with many lobes and much puckering. This is one of 

 our old names which has outgrown its usefulness, in that 

 too many diversified forms were included under the one 

 head, and it became necessary to subdivide and introduce 

 a large number of new names. These forms of shell are 

 very characteristic of jNIesozoic, and, though not known 

 from Victoria, the other States contain many of these 

 shells yet to be worked out, though some have already 

 been reported on. Champion Bay, Western Australia, is- 

 one of our best localities for certain types, whilst others 

 may be procured from the Lake Eyre Basin, Central Aus- 

 tralia ; White Cliffs, New South Wales j and the Rolling; 

 Downs Formation, Queensland. 



Belemnites are another INIesozoic group quite as typical; 

 as the Ammonites, and belong also to the Cephalopoda^ 

 They are ancient relatives of the living squid, with a 

 strong, solid, calcareous end, or guard, resembling a 

 pencil. Some of these have been so exceptionally well 

 preserved as to show the impression and position of the- 

 so-called inkbag of the creature. These are usually 

 to be found associated with the preceding, so that the locali- 

 ties already given will suffice here also. Very many other 

 forms of life were also abundant in Palaeozoic and Meso- 

 zoic times, but mention need only be made in this place 

 of the armour-plated fishes of the former (especially of 

 the Devonian portion), and the gigantic extinct reptiles 

 and sea-lizards (such as the Dinosaurs and Ichthyosaurs) 

 of the latter. These forms have given rise to the popular 

 idea of referring sometimes to the Palseozoit as the " Age 

 of Fishes," and the Mesozoic as the " Age of Reptiles." 

 Palaeozoic time also had its characteristic plants, and 

 these accumulated in such abundance in some places as to 

 give us our most valuable coals of the present day. Such 

 plants as the Lycopodiacese, or club-mosses, allied in 

 some respects to the living Lycopodium, another group 

 commonly known as horse-tails, as well as an important 

 series of ferns, made up the main features of this ancient 

 flora. 



Mesozoic time likewise had its own particular predomi- 

 nating types of plants, which may be briefly indicated as 

 Cycads and Conifers, and these also have in many places 

 formed important coal seams. 



