DALL: MOLLUSCA AND BRACHIOPODA. 409 
Lima martiali Mabille et Rochebrune, Miss. du Cap Horn, Moll., 1889, p. H.124; 
Orange Harbor. 
Inma (Limatula) pygmaea Smith, Chall. Rep., Lamell., 1885, p. 292. 
U.S. 8. “ Albatross,” station 2777, Magellan Straits, in 20 fathoms, gravel ; 
U.S. N. Mus. 96,192; also at station 2778, in 61 fathoms, bottom temperature 
47°.9 F. Kerguelen Island, Smith; South Orkneys, Scottish Antarctic 
Expedition ? 
From the material available it seems that there are two species of Limatula in 
the Magellanic region, one of which was described as above indicated, by Philippi, 
as having smooth radial ribs and the submargins without radial sculpture. 
One form, which I identify as pygmaea, has the smooth submargins large, and 
extending nearly to the ventral border, without any radial sculpture upon them 
whatever, and with the concentric sculpture of the disk confined to incremental 
lines. The number of ribs visible at the ventral margin does not exceed fifteen. 
Tn neither of the species is there any medial sulcus. The very young show a dis- 
tinct though minute taxodont provinculum, but the adult does not show the 
hinge denticulations of Zimaea; although the general form and sculpture recalls 
Limaea rather than the Limatula of the Northern hemisphere. 
Lima (Limatula) falklandica A. Apams. 
Limatula falklandica A. Adams, P. Z. 8. Lond., 1863, p. 509. 
? Lima (Limatula) hodgsoni KE. A. Smith, Nat. Antarct. Exp., Nat. Hist., 1907, 2, 
Moll., p. 6, pl. 3, fig. 8. 
U.S. 8. “ Albatross,” station 2781, off the coast of Southern Chile, or West- 
ern Patagonia, in 348 fathoms, mud, bottom temperature 49°.9 F. U.S. N. 
Mus. 96,930. Also at stations 2783, 2784, and 2787, in 61 to 194 fathoms, mud, 
temperatures 48° to 54° F. Falkland Islands, A. Adams; South Orkneys, 
Scottish Antarctic Expedition. 
This species, of which a good many specimens were collected, differs from 
L. pygmaea Philippi, by having short and very small, smooth submargins, and in 
having the radial ribs smaller, much more numerous, and obscurely divided into 
three areas ; the median with about fifteen strong ribs; an anterior with about 
eleven gradually much smaller ribs ; and a posterior with about fourteen similar 
ribs, gradually becoming obscure. All these ribs are elegantly sculptured by 
small concentric, regularly spaced lamellae, which in crossing the ribs rise to 
small vaulted scales exactly as figured by Smith for Z. hodysoni, as above cited 
(fig. 8b). In some cases the scales are closer than in others, but this seemed the 
only material variation. I am not sure that Z. hodgsoni is specifically identical 
with L. falklandica, since the former is more than twice as large as the latter, but 
the beautiful figure of the former given by Smith seems identical in every other 
respect with our shells. I separate falklandica from pgymaea + martiali, because 
A. Adams especially mentions the concentric sculpture, while Philippi and Mabille 
declare their shells to have “smooth”? ribs. 
