SO-CALLED " SOAPSTONE " OF FIJI. 7 



half of the exterior convolution ; surface beset witli small, irregular, 

 convex prominences, except in the region of the aperture, which, is 

 marked with radiating grooves or furrows ; aperture obscure, cres- 

 centiform, situated in a depression at the inner margin of the ter- 

 minal segment. Diameter -^-^ inch (0'5 millim.). 



This is a somewhat obscure organism, but it may, I think, be 

 safely referred to the genus Sphoeroidina^ though differing in point 

 of superficial ornament from any species hitherto described. Only 

 two specimens have been met with. It is possible that the minute 

 shells described provisionally under the name Discorhina pulvinata 

 ('Challenger' Report, p. 650, pi. 88. fig. 10), which exhibit very 

 similar surface-markings, may represent the immature condition of 

 the same species ; whether this be so or not, however, can only be 

 determined from the examination of a larger number of specimens 

 than are at present forthcoming. 



75. Tkun-catulina mundula, Brady, Parker, & Jones. 



A compact, neatly constructed variety of Truncatidina, described 

 and figured in a recent memoir on some Foraminifera from the 

 Abrolhos Bank (Trans. Zool. Soc. Lond. 1887, vol. xii. pt. 7, pi. xlv. 

 fig. 25, in the press). Morphologically it is a near ally of Truncatu- 

 lina Haidingerii^ but is less stoutly built and has nearly double the 

 number of segments in each convolution ; the periphery is usually 

 sharp, and the sutures on the superior face are marked by a certain 

 amount of thickening of the shell-wall. Its nearest isomorph is 

 Pulvinulina Karsteni. 



On the Abrolhos Bank it is common at 260 fathoms, but the form 

 is by no means rare in tropical seas. 



It may be here observed that the specimens assigned in the Table 

 to TruncatuUna Haidingerii and Tr. Akneriana do not in either case 

 present quite the typical characters of these species, as portrayed in 

 d'Orbigny's " Yienna-Basin " monograph. The differences, however, 

 are in comparatively trifling details, and not sufficient to demand 

 separate specific treatment. 



The remains of a few Ostracoda were found associated with the 

 Poraminifera, but they were for the most part imperfect and otherwise 

 in poor condition. These have been examined by my brother 

 Dr. G. S. Brady, who writes as follows concerning them : — " Some, 

 if not identical, approach very closely certain of the ' Challenger ' 

 species. In fact no doubt there is Krithe producfa, a common recent 

 species in the southern hemisphere ; and there are valves which may 

 be referred with some little reservation to CytJiere dictyon and 

 CytJiere arata ; but this is all that can be said." 



Turning now to the question of geological age, there need not, I 

 think, be the slightest hesitation in assuming the Post-tertiary origin 

 of the deposits under consideration. Of the ninety-two species 

 of Poraminifera which have been identified, eighty-seven are forms 

 still living in the neighbourhood of the Pacific islands ; whilst the 

 remaining five, two of which are new to science, are all extremely 



