DALL: MOLLUSCA AND BRACHIOPODA. 411 
TELEODESMACEA. 
(D10GENODONTA). 
Astartacea. 
Astartidae. 
ASTARTE Sowersy. 
Astarte longirostra Orzieny. 
Falkland Islands, Orbigny, Straits of Magellan, U. S. S. ‘ Albatross,” at 
station 2778, in 61 fathoms, bottom temperature 48° F. U.S. N. Mus. 110, 
711. Elsewhere in depths as little as 20 fathoms, but rare apparently everywhere. 
The variations of this shell are considerable. Orbigny figured one with excep- 
tionally long umbones, and the more common mutation with shorter beaks has 
received the name of 4. magellanica from H. A. Smith. 
Cyrenacea. 
CORNEOCYCLAS Fervssac. 
Corneocyclas Ferussac, ex parte, Dict. Sci. Nat., 1818, 12, p, 278; Dall, Trans. 
Wagner Inst. Sci., 1903, 3, p. 1459. 
Pisidium C. Pfeiffer, Naturg. Conch., 1821, 1, p. 123. 
Corneocyclas magellanicus Datt, n. sp. 
Shell small, whitish, with an olivaceous smooth periostracum, low, wide beaks, 
and polished surface with faint concentric indications of three or four resting 
stages; form inequilateral, anterior end shorter, bluntly subtruncate; base 
evenly rounded; posterior end slightly attenuated and rounded; external sculp- 
ture of faint incremental lines, chiefly obsolete between the resting stages; in- 
terior smooth, white; hinge of right valve with a single feeble horizontal tooth 
directly under the beak, and two well-developed lateral teeth rather distant from 
the beak, the posterior lateral stronger. Length of shell, 3.5; of posterior end of 
shell, 1.8; height, 2.5; diameter (of both valves), 2.0 mm. 
U.S. S. ‘ Albatross,” station 2778, in Magellan Straits, in 61 fathoms; one 
right valve. : 
A single right valve, evidently washed into the sea from some stream, was 
obtained as above. As no species of this genus has been reported from this 
region I have thought it best to put it on record. The beak is not in any way 
differentiated or set off from the general surface of the shell. 
