84 DE. T. DAVIDSON ON EECENT BRACHIOPODA. 



truncated by an incomplete, longitudinally oval foramen, margined anteriorly by the 

 ximl)0 of the dorsal valve and by two small lateral triangular deltidial plates ; beak-ridges 

 not very sharply defined. Surface of valves smooth, strongly punctate, and marked by 

 fine concentric lines of growth. The apophysary system in dorsal valve composed of 

 a doubly attached loop extending to about two thirds of the length of the valve, first 

 attached to the base of the hinge-plate, the principal stems widening gradually and, 

 at about half their length, becoming attached to the upper edge of an elevated median 

 septum, then again extending towards the front before becoming reflected. Colour light 

 whitish yellow. Length 4^, breadth 3|, depth 2| lines. 



Hab. Homsund and Bellsund, Spitzbergen, 40 to SO fathoms (Torell) ; Wellington 

 Channel (Belcher) ; Shetland, 35 miles N.N.W. of Unst, in 90 to 100 fathoms ; Channel 

 Slope, about 185 miles from Cape Clear and Usliant, and 165 miles from the Scilly Isles, 

 in 358 fathoms ; Channel Slope, 339 fathoms ; otf Cape St. Vincent on the coast of Spain, 

 292 fathoms (Jeffreys) ; Gulf of St. Lawrence (P. P. Carpenter and Whiteaves) ; Japanese 

 Waters (A. Adams) ; off Iceland (' Valorous ' Expedition) ; Possil at Uddevalle (Hisinger 

 and Jeffreys) ; and in another raised bank near Christiauia in 1866 by Messrs. Crosskey 

 and Robertson. 



Ohs. I have seen a number of specimens of this small well-marked species ; none of 

 them exceed the dimensions above recorded. Terebratella spitzbergensis evidently 

 enjoys an extended geographical range. 



In 1834 Sir Charles Lyell collected in a Swedish postglacial deposit a single ventral 

 valve of this brachiopod, while investigating the proofs of a gradual rising of the land 

 in certain parts of Sweden. He simply called it a Terebratula, and gave two figures of it 

 in the ' Philosophical Transactions ' of the Royal Society for 1835. According to Torell 

 the species was confounded in 1837 by Hisinger with TerebraMina caput-serpentis. 

 In 1852 I described and figured the shell in the Ann. «& Mag. Nat. Hist, from a 

 perfect specimen lent to me by Mr. H. Cuming, and then gave it the name of Terebratella 

 Spitzbergensis, which it has since retained. In 1859 Torell published an incomplete 

 figure of the loop, but sufficient to show that it was doubly attached as in Terebratella. 

 The young of Terebratella spitzbergensis have not yet been examined; but in a paper by 

 Herman Priele on 'The Development of the Skeleton in the genus Waldheimia,' a. whole 

 plate is devoted to enlarged illustrations of the loop, and the author remai^ks that in one 

 example " remnants of the lateral walls are still left on the lamel-processes at their point 

 of connection with septum, which signifies an earlier stage like that in Tf^aldheimia." 



42. Tekebbatella btjbicunda, G. B. Sowerby. (Plate XV. figs. 15-29.) 



? Terebratella sanguinea, Quoy & Gairaard, Voyage de TAstrolabe, Zool. vol. iii. p. 556, pi. 85. figs. 7-8, 

 1834 (not T. sanguinea, Cbemnitz). 



Terebratella rubicunda, G. B. Sowerby, Proc. Zool. Soc. 1846, p. 92, and Tbes. Coucb. i. p. 351, 

 pi. kx. figs. 45-47, 1846. 



Terebratella inconspicua, Sowerby, Proc. Zool. Soc. 1846, p. 93, and Tbes. Concb. p. 359, pi. Ixxi. 

 figs. 102-104, 1846. 



II alionia Fatewdewwem, Davidson, Ann. & Mag. Nat. Hist. 2ud ser. vol, v. p. 475, pi. xv. fig. 1, 1850. 



