222 "TERRA NOVA" EXPEDITION. 



Pohjliriiin miniaceuni. Mobius, 1880, FM. p. 85, ])1. vii. 



Brady, 1884, FC. p. 721. pi. c, figs. 5-9. pi. -ci. fig. 1. 

 '„ „ ScWumberger, 1892, FAM. p. 196, fig. 5. 



Chapman, 1899 FFA. p. 16, pi. iv, fig. 7. 

 ,, „ Merkel, 1900, Beitrage zur Kentniss des Baiios von Polylrema 



miniaceum, Zeitsclir., f. wiss. Zool. Bd. Ixvii. ])p. 291-322, pis. 

 xvi, xvii. 

 Sidebottom, 1904, etc., RFD. 1909, p. 11, pi. iv, fig. 7. 

 Hickson, 1911, P. {entire paper), pis. xxx-xxxii. 

 Heron-Allen and Earland, q.v. re Risso. 1914. etc., FKA. 1915. p. 728. 

 Ciisliman, 1919, RFNZ. p. 632. 



Heron-Allen and Earland, 1920, V.P.. p. 165 ; 1922, Bull. Soc. Sci. Hist. 

 and Nat. Corse. (Bastia, Corsica). In the press. 



Stations 1-6. 



The abimdance of thi.s species in tlie N.Z. area, and especially at Station 2, 

 where practically every solid organism is more or less covered witli it. has 

 enabled us to make a noteworthy contribution to tlie large body of facts which have 

 already been recorded about this genus, and our observations have been amplified 

 by the examination of an unlimited supply of material from the " sables rouges " 

 of Ajaccio (Corsica) which seemed to us to promise so much light upon the sub- 

 ject that we proceeded thither for the pm-pose of coUectmg and studying the 

 organism. Our journey was amply repaid. 



Early " Free " Stage. — Carter, in 187G (P., p. 196). in referring to " one 

 mounted, rounded, embryonic specimen from Mauritius," appears to have antici- 

 pated Schlumberger in the discovery of the free stage in the life-history of this 

 organism, but, beyond this brief statement, does not seem to have followed the 

 matter up. Schlumberger {ut supra) describes, and figures a transverse section 

 of, the free organism ; he states that " it shows three spherical chambers with 

 their walls traversed b_v a few perforations, and arranged like the embryonal 

 chambers of a Globigcrina, except that one cannot demonstrate any special 

 opening between one chamber and another. Around these three chambers it forms, 

 irregularly, a covering layer of chambers of all shapes and sizes. They have 

 thick walls traversed by strong perforations which increase in diameter from the 

 interior to the exterior. The succeeding (outer) chambers are often drawn out 

 into points, incorporatmg sand-grains in their walls, and end by fixing the 

 embryo to some submarine body." In otu' experience the feature of the drawn- 

 out chambers is rare, but we have admirable examples from Ajaccio. This free 

 stage was described and figured again by Sidebottom from Delos (ut supra.). 



The abundant supply of free individuals placed at our connnand enables us 

 to make some additions and corrections to the foregoing. The smallest specimens 

 observed in the free state (Figs. 1-3) are flattened and consist of four chambers, 

 two of them of comparatively large size, apparently connected with one another 

 by an intermediate neck, and liavuig two smaller chambers filling up the curves 

 (equitant) between the neck and the two larger chambers. The whole organism 



