FOEAMINIFEEA OF THE KEEIMBA AECIIIPELAGO. 730 



456. Polystomella verriculata Brady. 



Polystomella vnrriculata Era(\v, 1879, etc., RRC. 1881, p. 66. 



Brady, 1884., FC. p. 738, pi. ex. fig. 12. 

 Chapman, 1907, RFV. p. 142, pi. x. fig. 10. 

 Sidebottoiii, 1904, etc., RFD. 1909, p. 15, pi. v. fig. 3. 



2 Stations. 



Brady's species is represented in these dredgings by two typical specimens only, one 

 each at Stus. 8 and 10, characterized by the thin compressed shell with practically 

 parallel faces, the surfaces of which are covered by a network of ridges interlacing 

 between the limbate sutures. The peripheral edge is acute and entire. At Stn. 9 

 some specimens were found presenting characters intermediate between Brady's type 

 and the type figured by Millett under Brady's specific name. 



Millett's figure is, in our opinion, sufficiently distinct to be separated as a new 

 species, for which we propose the name P. milletti. None of the clearly allied 

 varieties described by E. J. Goddard from sand dredged 22 miles east of Sydney 

 (80 fms.) (Rec. Austral. Mus. vol. vi. 1906-7, p. 306) and by H. I. Jensen under 

 the name P. hedleyi (Proc. Linn. Soc. N.S.W. vol. xxix. 1905, p. 828, pi. xxiii. fig. 4; 

 and vol. xxxii. 1907, p. 291), which would appear to connect P. verriculata and 

 P. milletti, being decorated with " septal bridges very irregularly developed," were 

 found at Kerimba. 



457. Polystomella milletti, sp. n. (Pi. Llll. figs. 38-42.) 



"^Polystomella verriculata Millett, 1898, etc., FM. 190-J, p. 601, pi. xi. fig. 3, 

 15 Stations. 



Test free, consisting of two to three convolutions, the last consisting often to twelve 

 chambers, somewhat inflated, sutural lines depressed, no retral processes visible. 

 Periphery more or less lobate. Excavated in the umbilical region, which is filled up 

 with a deposit of secondary shell-matter in the form of fine beads. This deposit 

 obscures the segmentation of the early convolutions and renders them difficult to 

 follow even in a balsam mount. Tlie beaded structure extends from the umbilical 

 region into the sutural depressions, but over the surfaces of the chambers the beads 

 coalesce and form short ridges usually arranged in chevrons, with tlie angle pointing 

 towards the periphery of the shell. On the septal face of the shell the beads are 

 often produced into short sharp spines covering the entire surface ol the face and its 

 immediate neighbourhood. 



This particularly handsome species is one of the most characteristic of the Kerimba 

 types, occurring at practically every Stn. and often in considerable numbers. It appears 

 to be veiy closely allied to, if not identical with, the form figured by Millett as 

 P. verriculata Brady, although his specimens are described as " reticulate on tlie 



VOL. XX. — PA.RT XVII. No. 25. — November, 1915. ■ 5 ic 



