OF CONCHOLOGY. 135 



Hah. New Zealand, Coll. Cuming. 



This species has been referred to recently by Messrs. David- 

 son and Reeve, as the adult of Waltonia Valenciennesii, Dav., 

 an immature ? brachiopod previously described. For reasons 

 elsewhere stated I have thought it best to retain the original 

 name until more is known. 



Magasella flexuosa. 



" T. magellaniea, var.," Reeve, MSS. label. 



? Terehratida flexuosa^ King, Zool. Journ. vol. v, p. 337. Sby., 



Thes. Conch, vii, p. 347, pi. 69, fig. 23, 24. 

 ? TerehrateUa flexuosa, Gray, B. M. Cat. p. 87. Dav., An. 



Nat. Hist. 1861, p. 38. H. and A. Ad., Gen. Rec. Moll. 



ii, p. 576. 

 TerehrateUa 3IageUanica, Reeve, Conch. Icon. pi. ? fig. ? 



Journ. de Conchyl. 1861, p. 127. 



JIah. Straits of Magellan, Orange Harbor, Ex. Exp. Smith- 

 sonian Cabinet, 11783. 



I am not sure this is King's species as I have not had access 

 to the Thesaurus, but it is certainly not a TerehrateUa, though 

 it resembles T. dorsata externally. 



Shell dull reddish brown, solid, transversely ovate ; neural 

 valve strongly bicarinate, emarginate, provided with about 28 

 strong, sharp, divaricate, radiating ribs or plications somewhat 

 imbricated by the lines of growth. Margin of the valves strongly 

 flexuose. Neural valve somewhat arched by the carinas, other- 

 wise the shell is moderately compressed. The beak is short and 

 wide, false area smooth, except for lines of growth, and cari- 

 nated at the edges ; wide and narrow ; deltidia long, narrow and 

 slightly separated. Apex slightly recurved, foramen circular, 

 incomplete. Apex of haemal valve flattened, nucleus acute but 

 inconspicuous. Cardinal process prominent, bifid, excavated at 

 its extremity ; hinge plate moderate, excavated, centrally 

 grooved and laterally bicarinate ; from the carinations spring 

 the apophyses. Beneath the hinge plate there are two cavities, 

 one on each side of the septum, extending into the beak. The 

 mesial ridge, deeply grooved above, extends from the septum 

 under the hinge plate to the middle of the shell, when the true 

 septum rises abruptly. It is slender, angulated and extending 

 obliquely forward meets the haemal processes, which give off a 

 triangular web of shelly matter to its upper edge. Leaving the 

 hinge plate at the terminations of the lateral carinations, two 

 short, slender, pointed crura are curved inward, and the haemal 

 processes curve roundly, to meet the septum as before described. 



