54 
AUSTRALASIAN ANTARCTIC EXPEDITION. 
Tertiary marine faunas are known from South America (Chile, Argentine, and 
Patagonia), the Antarctic (islands in the Weddell Sea), New Zealand, Tasmania and 
south-east Australia, i.e., only in the southern circum-Pacific lands. The greater part 
of the beds containing them belong approximately to the same age, variously estimated 
in the different countries and by different authors from Eocene to Miocene. Following 
Buckmann, I shall term it the Oligocene-Miocene. In New Zealand and South America 
there are also still younger faunas, which are generally referred to the Pliocene. 
The following list shows the genera of which these Oligocene-Miocene faunas 
are composed : — 
South America. — 
(a) Chile—“Magellania,” Megathyris, Discina. 
( b ) Argentine and Patagonia —Hemithyris, Aetheia, Terebratulina, Bou- 
chardia, Pachymagas, Terebratella, “ Magellania.” 
Antarctic.—Lingula, Hemithyris, Terebratulina, Liothyrella, Bouchardia, 
Magella, Pachymagas, “ Magellania.” 
New Zealand.—Thecidellina, Aetheia, Hemithyris, Terebratulina, Murravia,* 
Liothyrella, Argyrotheca,* Bouchardia,* Magadina, Rhizothyris, 
Stethothyris, Pachymagas, Neothyris, Gyrotliyris, Magella, Tere¬ 
bratella. 
Australia. -Crania, Lacazella, Hemithyris, Terebratulina, Murravia, Liothyrella, 
Megerlina,* Aldingia, Magadina, Magadinella, Rhizothyris.* Steth¬ 
othyris, Magella, Terebratella, Magellania. 
Probably further study will show a still greater number of common genera in the 
above districts. Meanwhile they suffice to show the source of the most important 
elements of the Recent fauna. Thus the younger Tertiary (Wanganuian) fauna of 
New Zealand, so far as it is at present known, is a direct development of a small section 
only of the older Tertiary (Oamaruian) fauna, and consists only of the genera Hemithyris, 
Terebratella and Neothyris, including the majority of the Recent species of these genera 
in the New Zealand area. The remaining elements of the Recent fauna include one 
genus, Liothyrella, not known from the Wanganuian, but common in the Oamaruian, 
and only two genera not recorded fossil from the area, viz., Crania and Amyhithyris. 
There can be little doubt that they will yet be found fossil in the Tertiary. The Recent 
New Zealand fauna is merely a diminished remnant of the rich Oamaruian fauna, and 
needs no land connections since the Miocene to explain its character. If later migrations 
to and from Australia had been possible, we should expect to find, e.g., Magellania in 
New Zealand and Neothyris in Australia. The specific and generic distinctness of the 
Recent New Zealand and Australian faunas precludes any land connections between 
the areas in the Pliocene or Post-Pliocene. 
* Determinations hitherto un published. A new species of Bouchardia occurs in the Mount Brown beds, Canterbury, 
and of Argyrotheca in the limestone of Flat Top Hill, Oamaru, New Zealand. 
Murravia catinuliformis (Tate) is found in the glauconitic limestone of Land on Creek, Oamaru, New Zealand . 
Waldheimia corioensis McCoy is a species of Rhizothyris. A new species of Megerlina is included in Mr. It. N. Atkinson’s 
collection of fossils from Table Cape, Tasmania, 
