FORAMINIFERA— HERON-ALLEN AND EARLAND. 137 



10 and 11 all the typical non-limbate specimens bear a spine at tlie initial 

 extremity. At Station 10 the species appears to be subject to great abnormalities. 

 Among the " freaks '" observed were many instances of marked depauperation at 

 half growth, succeeded by recovery, giving a lyriform outline to the test. Other 

 instances of spiral twists in the axis, reversed axes, and fracture and repair of 

 the shell, the best instance of which was found at Station 6. 



201. Bolivina limbata. Brady. 



BoUvina limbata, Brady, 1879, etc., RRC. 1881, p. 57 ; 1884, FC. p. IIU, pi. liii, tigs. 26-28. 

 Heron-Allen and Earland, 1914, etc., FKA. 1915, p. 646, pi. L, fig,s. 1-4. 



Station 2. 



A good specimen. 



Sub-Family CASSIDULININAE. 

 CASSIDULINA, d'Orbigny. 



262. CassiduUna laevigata, d'Orbigny. 



Cassidulina laevigata, d'Orbigny, 1826, TMC. p. 282, No. 1, pi. xv, figs. 4, 5. 



Heron-Allen and Earland, 1914, etc.. FKA. 1915, p. 6-52. 



Stations 1-9, 11, 27, 31. 48, 55 (-f K. I., E. d. J., D.). 



Generally distributed, but never very abmidant. The best Stations were 

 No. 6 in the N.Z. area, and Nos. 27, 31 in the Antarctic. The predommant 

 type at all Stations, except Stations 2 and 3, is a sharply-keeled form, Brady's 

 fig.- 3 (FC. pi. liv). At Stations 2 and 3 the original form figured in the 

 '■ Tableau Methodique " appears in company with the carinate form. At Station 

 a double specimen, due to what, at present, we regard as fusion of 

 primordial chambers. 



263. Cassidulina laevigata, var. fuinida, nov. PI. V, figs 8-10. 



Stations 1, 2, 3. 



Chambers arranged as in the type, but dift'ering in the structm'e of the shell, 

 which is strongly biconvex and very thick walled. Sutures obscure but, when visible, 

 strongly limbate. Surface of the shell often slightly rough. Peripheral edge rounded ; 

 never keeled. 



This variety, which is very distinctive, can hardly be mistaken for the type 

 or any of the many figured forms attributed to C. laevigata. The outstanding 

 feature is the extraordinary thickness of the shell-wall, which has the appearance 

 of being deposited in layers, as the latest formed chambers are usually thinner 

 walled and clearly distinguishable in outline, whilst all the earlier ones in the 

 same individual have become almost indistinguishable from one another. It 

 is very local, occurring only at Stations 1, 2 and 3, where, however, it is perhaps 

 more abundant than the typical C. laevigata, which also occurs at these Stations. 



Size :— Breadth, • 30- -40 mm. ; thickness, -20- "25 mm. 



