1878.] Mr. T. Davidson. On Brachiopoda. 437 



by the expedition. The shell is large, trigonal, broadest anteriorly, 

 tapering posteriorly ; valves moderately convex, somewhat flattened 

 along the middle, and abruptly bent inwards close to the margin. The 

 loop is short, simple, and rendered annular by the union of the oral 

 processes. The surface of valves is marked by fine radiating lines ; 

 length 63, width 50, depth 35 millims. 



A unique specimen of this fine species was dredged off Culebra 

 Island, to the north-west of St. Thomas, in the West Indies, at a depth 

 of 390 fathoms. 



Terebratulina Wyvilli greatly exceeds in dimensions the largest 

 known species of the sub-genus both recent and fossil. 



4. Terebratula or Terebratulina (?) Dalli, n. sp. 



Of this small shell only one dead specimen was dredged, measuring 

 8 millims. in length by 5| in width, and 4 in depth. The loop was 

 incomplete, but seems to have been short as in Terebratula and 

 Terebratulina. In shape the shell is longitudinally oval, thin, globose, 

 glassy, and semi-transparent, slightly depressed anteriorly. Exteriorly 

 the surface of valves is covered with fine radiating striee, with shorter 

 ones interpolated between the larger ones. It was dredged in lat. 34° 

 37' W., long. 140° 32' E. ; depth 1,875 fathoms, together with Distinct 

 Atlantica. 



5. Terebratulina (?) Murrayi, n. sp. 



Of this species some eleven examples were dredged. It is a small 

 shell not exceeding 4 millims. in length by 3^ in width, and 2 in depth. 

 In external shape it is obscurely trigonal, about as broad as long ; 

 broadest anteriorly, tapering posteriorly, white, surface marked by a 

 small number of strong radiating ribs. Loop short, simple. Dredged, 

 lat. 28° 33' S., long. 177° 50' W., near Kermadoc Isle, south of Fejee 

 Isles, in a depth of 600 fathoms. 



This is a remarkable and puzzling species, for while its shell and 

 loop partake of the character of Terebratulina, its labial appendages 

 seem to differ very materially from those of the sub-genus to which it 

 is provisionally referred. 



6. Walclheimia Kerguelensis, n. sp. 



Of this fine species a great number of specimens were dredged by 

 the ' Challenger ' Expedition off Marion Island, west of Kerguelen 

 Isle, in a depth of 100 fathoms, and also in lat. 50° 4' S., long. 71° 

 22' E., at a depth of 150 fathoms. 



The shell is elongated oval, ventricose, smooth, yellowish-white; 

 ventral valve deeper than the dorsal one, and more or less prominently 

 keeled by the presence of a wide, slightly convex fold, and in the 

 dorsal valve by a slight mesial depression or sinus commencing about 



