40 BULI.ETIN 104, UNITED STATES NATIONAL MUSEUM. 



Lagena orhignyana Balkwill and Wuigiit, Trans. Roy. Irish Acad., vol. 

 28, 1885, p. 341.— H. B. Beady, Journ. Roy. Micr. See, 1887, p. 90G.— 

 Peakcey, Trans. Glasgow Nat. Hist. Soc, vol. 2, 1890, p. 177. — 

 WiUGHT, Ann. Mag. Nat. Hist., vol. 6, ser. 5, 1890, p. 124; Proc. Roy. 

 Irish Acad., ser. 3, vol. 1, 1891, p. 481. — Robertson, Proc. Nat. Hist. 

 Soc. Glasgow, pt. 3, 1892, p. 241.— Wright, Irish Nat., vol. 9, No. 

 3, 1900, p. 54.— Earland, Journ. Quekett Micr. Club, ser. 2, vol. 9, 

 No. 57, 1905, p. 214. — Heron-Allen and Earland, Journ. Roy. Micr. 

 Soc, 1907, p. 426. — Balkwill and Millett, Rec. Foram. Galway, 1908, 

 p. 0. — Heron-Allen and Earland, Proc. Roy. Irish Acad., vol. 31, 

 pt. 64, 1913, p. 90; Trans. Linn. Soc. London, ser. 2, vol. 11, 1916, p. 

 253 ; Journ. Roy. Micr. Soc, 1916, p. 40. 



Description. — Test compressed, inflated in the middle, the central 

 body portion of the test nearly circular, apertural end slightly ex- 

 tended, periphery with a thin keel running entirely about the test, 

 at either side of which is a secondary lateral keel, slightly raised 

 above the general surface; wall smooth, finely punctate, test with 

 an entosolenian neck. 



Length not exceeding 0.40 mm. 



Distribution. — I have had numerous specimens from off the Brit- 

 ish Isles which are of this typical form figured by "Williamson and 

 in that region it is one of the common species. Although there 

 are numerous records for the species elsewhere, the figures given 

 show that the typical form was not that figured by the authors from 

 other regions. I have failed to find any typical material in the 

 western Atlantic, but the species is represented there by numerous 

 varieties. 



This short, nearly circular form figured by Williamson may be 

 taken as the typical form of the species. It is most simjDly charac- 

 terized by the peripheral keel and the secondary keel on either 

 side, dividing the test into tAvo distinct portions on either side, that 

 of the central part of the test inside the ring formed by the sec- 

 ondary keel and the concave area extended around the test between 

 the peripheral and the secondary keels. These two areas become 

 variously ornamented and changed in their relation to one another, 

 but these changes seem to be rather constant and show definite geo- 

 graphical limits in their distribution. 



LAGENA ORBIGNYANA (Seguenza), var. ANTILLEA, new variety. 



Plate 7, figs. 10, 11. 



Description. — Variety differing from the typical in the very large 

 size, in the ornamentation, which consists of tubular radiate mark- 

 ings in the peripheral keel, the secondary keel marked by a series of 

 pits which extend in on to the body of the test itself, and extend up 

 both sides of the apertural neck, nearh^ to the aperture itself; wall 

 ver}' thick, opaque. 



