484 
THE VOYAGE OF H.M.S. CHALLENGER. 
Lagena guinquelatera, H. B. Brady (Pl. LXI. figs. 15, 16). 
Lagena guinquelatera, Brady, 1881, Quart. Journ. Micr. Sci., vol. xxi., N. S., p. 60. 
Test elongate, compressed equally on five sides ; broadest below the middle, tapering 
gradually to a point at the oral extremity ; inferior end obtuse or rounded, sometimes 
apiculate ; peripheral angles sharp or carinate ; surface smooth or very faintly striate ; 
aperture ectosolenian. Length, about ^th inch (0 - 36 mm.). 
This is a symmetrical five-sided modification of Lagena Icevis, with a short tapering 
neck. 
It occurs in the South Pacific, north of the Society Islands, at a depth of 2350 
fathoms, and in the Southern Ocean, off Prince Edward’s Island, 50 to 150 fathoms. 
Lagena orbignyana, Seguenza, sp. (PI. LIX. figs. 1, 18, 24-26 ; winged variety, fig. 20). 
Entosolenia marginata (pars), Williamson, 1858, Rec. For. Gt. Br., p. 9, pl. i. figs. 19, 20. 
Fissurina orbignyana, Seguenza, 1862, Foram. Monotal. Mess., p. 66, pl. ii. figs. 25, 26. 
„ romettensis, Id. Ibid. p. 66, pl. ii. fig. 24. 
Lagena tridnda, Giimbel, 1868, Abh. d. k. bayer. Ak. Wiss., II. Cl., vol. x. p. 606, pl. i. fig. 8, a. 1. 
Fissurina marginata, var. tricarinata, Reuss, 1870, Sitzungsb. d. k. Ak. Wiss, Wien, vol. lxii. 
p. 468, No. 19a. — Schlicht, 1870, Foram. Pietzpubl, pl. iv. figs. 1-3 
(ectosolenian form). 
„ tridnda, Terquem, 1883, M6m Soc. g6ol. France, ser. 3, vol. ii. Mem. III. p. 30. 
pl. i. fig. 19, a. b. 
„ tricarinata, Id. Ibid. p. 31, pl. i. figs. 25-28. 
Some confusion has existed with respect to the compressed and carinate varieties of 
Lagena, wdiich appears to be due, in part at any rate, to Williamson’s illustrations of 
Entosolenia marginata. 
The original drawings of Lagena marginata (Test. Min., pl. i. fig. 7) represent a com- 
pressed pyriform shell with thin somewhat carinate periphery, not unlike fig. 21 of 
Williamson’s Monograph, or Pl. LIX. fig. 22 of the present Beport. The external orifice 
of such forms is generally Fissurine. 
There is, however, a very distinct variety in which the convex body of the shell, on 
both faces, is bordered by a raised edge in addition to the peripheral keel, and when 
this feature is conspicuously developed, the test appears to have three nearly parallel 
carinse, of which the central one is widest. The peculiar contour of the test is best seen 
in the end view (fig. 24, b., or 26, b.). Williamson’s figures (19, 20) manifestly pertain 
to this variety rather than to the true “ marginata .” They represent excellently the small 
specimens common in the British seas, but are wanting in the strongly marked features 
displayed by those inhabiting deeper water. 
Of the numerous names which have been applied to the “ tricarinate ” as distinct from 
the “ marginate ” form, one of those proposed by Seguenza takes precedence. 
