92 DK. T. DAVIDSON ON RECENT BRACHIOPODA. 



48. Teeebkatella Frielii, Davidson. (Plate XVI. figs. 16-17 h.) 



Terehratella Frieli, Davidson, Proc. Royal Soc. xxvii. p. 438, 1878 ; and T. frielii, Report on the 

 Brachiopoda, Voyage of H.M.S. ' Challenger/ Zool. vol. i. p. 46, pi. iii. figs. 19, 20, 1880. 



Shell small, ovate, slightly longer than vfide, smooth, white. Dorsal valve moderately 

 convex, slightly flattened or depressed anteriorly. Ventral valve deeper than the dorsal 

 one. Beak short, truncated by an incomplete foramen, laterally margined by two very 

 short and small deltidial plates. In the interior of the dorsal valve, the loop, which 

 extends to about two thirds of the length of the valve, is doubly attached, first to the 

 hinge-plate, and then to a mesial septum. Length 5 lines, width 4 lines, depth 3 lines. 



ITab. Two small specimens were dredged off Halifax by the ' Challenger ' Expedition at 

 a depth of 1340 fathoms ; and two other examples close to the Philippine Islands, in 82 to 

 102 fathoms. 



Obs. 1 feel much uncertainty, as I have stated in my ' Challenger ' Ueport, with respect 

 to the identification of the two small immature shells above described. I forwarded one 

 of them to Mr. Dall for examination, and he wrote back that he could not positively 

 identify it with any of the described species. Dr. Gwyn Jeffreys expressed a similar 

 opinion, adding that the septum and ccecal tubercles are very peculiar and remarkable, 

 and that he felt certain that it was an undescribed species of Terehratella. I therefore 

 give it here, merely for reference purposes. 



Subgenus Magasella, Dall, 1870. 

 To this subgenus six species have been referred, viz. : — 



1. Magasella flexuosa, P. King. 



2. crenulata, Sowerby. 



.3. aleutica, Dall. 



The following are uncertain species : — 



Magasella pataffonica, Gould. 



Icevis, Dall. 



MalvincB, d'Orbigny. 



4. Magasella Adamsi, Davidson. 



5. Gouldi, Dall. 



6. Cumingi, Davidson. 



Magasella incerta, Davidson. 



radiata, Dall. 



labradorensis, Sowerby. 



I am not, however, satisfied that even all those recorded as species can be definitely 

 accepted. "We know very little that is satisfactory about Magasella (?) crenulata, 

 Magasella aleutica, Magasella Adamsi, and Magasella Gouldi, and still less about the 

 six uncertain species. The material I have been able to collect was scanty and insuf- 

 ficient, and further investigations will be requisite whenever circumstances permit. It 

 is therefore at present not possible to determine which are really good species, which 

 varieties only, or synonyms. Magasella Jlexuosa and M. Cumingi are, however, good 

 species, and have been carefully studied. 



49. Magasella flexuosa. King, sp. (Plate XVII. figs. 1-5.) 



Terehratula flexuosa, P. P. King, The Zool. Journ. vol. v. p. 337, 1835. 



Terehratella flexuosa, Davidson, Ann. & Mag. Nat. Hist. 2ud ser. vol. ix. p. 367, 1852; Woodward & 

 Gray, Catalogue of the Brachiopoda in the British Museum, p. 87, 1853. 



