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ture. This form was only noted at three " Challenger" stations, 

 viz., Prince Edward Isle, Kerguelen and Bass' Strait, all in the 

 Southern Seas, and was dredged at moderate depths. Rather 

 scarce on seaweed bottom. North Arm. 



M. suhrotunda, Montfort. A very variable form, more com- 

 pressed than the former, with which it is linked by numerous 

 intermediate varieties. It has a wide distribution in shallow 

 waters. A common form on seaweed bottom ; less common on 

 mud banks. North Arm. 



M. ohlonga, Montagu. A cosmopolitan species, and found at 

 all depths. It is the commonest form of the genus in the Port 

 River, where it is generally distributed, but shows preference for 

 muddy bottoms. 



M. labiosa, d'Orbigny. A few specimens occur which are very 

 irregular in growth, with crescentiform aperture and prominent 

 lips, which may belong to this species. In washings from sea- 

 weed, North Arm, and rare in small creeks near Pinery. 



M. seminulum, Linne. Typical specimens of this widely-dis- 

 tributed foraminifer are not common in the Port River, its place 

 being taken by the feebler form, 21. ohlonga. The examples are 

 small, occur sparingly in all the situations examined, but most 

 distinctly on muddy ground. ^ 



M. secans, d'Orbigny. One or two examples taken from sea- 

 weed ground are doubtful occurrences as living forms. 



2f. undosa, Karrer. The angles of chambers are marked by 

 sharp and wavy costse. A shallow-water species. The finest 

 examples of this form obtained on the "Challenger" cruise were 

 from East Moncoeur Island, Bass' Strait. In the Port River the 

 examples are small and not very characteristic. Only observed 

 from mud-banks. North Arm, where it occurs in considerable 

 numbers. 



2f. fusca, Brady. An arenaceous variety of the genus iso- 

 morphic with If. ohlonga, and is distinctively a brackish water 

 species, living in estuaries and pools at the mouth of rivers. It 

 is a common form in such situations on the British coast. Found 

 sparingly in brackish pools covered at high water near Birken- 

 head, and in moderate numbers on sandy bottoms in the small 

 creeks near the Pinery. 



M. (Triloculina) trigomda, Lamarck. Rare, in North Arm. 



Spieoloculina, d'Orhigny. 

 S. planulata, Lamarck. Rare, from seaweed-dredgings. North 

 Arm. 



