BY H. I. JENSEN. 831 



rocks from the Piper River in north-eastern Tasmania; they are 

 associated here, as at Pokolbin, with Stenopora, various Fenes- 

 tellidas and other Bryozoa; with marine gastropods and corals. 



Conclusion. 



In this investigation it was noticed that the classification of 

 Foraminifera into species is a matter of extreme difficulty, 

 especially in the larger genera. In such the species become 

 scarcely more than large varieties, a fact which bears out the 

 doctrines enunciated by Darwin in "Origin of Species." _ 



More work is needed on the distribution of our Foraminifera 

 both as regards depth and latitude. This kind of work is 

 especially interesting, as it shows how variable and deformed a 

 species becomes on leaving its normal habitat. Littoral species 

 partake of the characters of abyssmal forms on leaving shallow 

 water. Variability is very great in most species of Foraminifera, 

 as one would expect in such a lowly organised group. 



The Eocene and Permo-Carboniferous forms enumerated here 

 are only intended to supplement known records by the addition 

 of new localities. Most of these forms have already been recorded 

 by Mr. Howchin."^ 



EXPLANATION OF PLATE XXIII. 



Pig. 1. — Nodosaria scalaris, Batsch ( x 100). 



Fig. "2. — Lar/ena kevis, Montagu ( x SO). 



Fig. 3. — Polyjiiorphina fiororia, Keuss ( x 80). 



Fig. 4:.—Poly8tomella macella, Fichtel & Moll. ( x 40). 



Fig. 5. — Rheophax eimeta, n.sp. ( x 16). 



Fig. 6.-- ,, ,, single chamber ( X 20). 



Fig. la.— „ ,, (xl6). 



Fig. 7b.— „ „ ^ (xl6). 



Fig. 8. — Polymorphiyia alveolini/ormis, n.sp. ( x 10). 



Fig. 9.- „ „ (xlO). 



Fig. 10. — ,, ,, a specimen ground down on 



one side ( x 10). 

 Fig. 11. — ,, * ,, a specimen partly ground down 



on one side ( x 10). 

 Fig.l2a-6. — " ,, ,, transverse sections ( X 10). 



Fig. 13. — Lingulina carinata, Hantken, var. ( x 10). 

 'Fig.li. — Polystomella hedleyi, n.sp. { x 40). 



* Report Aust. Assoc, Adv. Sc. 1893, v. pp. 355, 365. 



