REPORT ON THE BRACHIOPODA. 37 



Terebratulina cailleti, Crosse (PL II. fig. 2, a). 



Terebratulina cailleti, Crosse, Journ. de Conch., 3""= ser., vol. v. p. 27, pi. i. figs. 1-5, 18G5. 

 Terebratulina cailleti, Pourtales, Bull. Mus. Comp. ZooL, Camb., Mass., vol. i., No. 6, p. 109, 



1867. 

 Terebratulina cailleti, Dall., Biill. Mns. Comp. Zool., Camb., Mass., vol. iii.. No. 1, 1871. 



Of this species only one minute example was dredged by the Challenger Expedition ; 

 it measures 2 mm. in length and breadth, and, consequently, is a very young immature 

 specimen. It seems to agree well with similar individuals of the species sent to me by 

 Professor Agassiz, which he had obtained near Barbados ; likewise with others dredged 

 by Barrett off Jamaica, as well as with some young shells of the same species which had 

 been obtained in 70 fathoms of water, in lat. 21° 48' S., and long. 40° 3' W. of Greenwich, 

 by the captain of the English Atlantic steamer "Norseman," and sent to me in 1877 by 

 Mr R. Rathbun. 



Of course, so young a shell does not exhibit the character of the adult condition ; it is 

 slightly ovate, with some nine simple rounded ribs and weU-defined interspaces ; the ribs 

 being likewise intersected by a few equidistant concentric lines of growth. When the 

 shell is adult the ribs are comparatively finer, and more numerous, with shorter ones 

 interpolated between the longer ones. Dr Gwyn Jeffreys considers Ter. cailleti to be 

 quite distinct from Ter. cajmt-serpentis. 



The single specimen from the Challenges Expedition was obtained at Station 122. 

 September 10, 1873, lat. 9° 5' S., long. 34° 49' W. to 53' W., off Pernambuco, Africa, in 

 350 fathoms. 



Terehratulina cancellata, Koch (PL I. figs. 11-16). 



Terebratulina cancellata, Koch, Conch. Cab., vol. vii., pi. ii. figs. 11-13. 

 Terebratulina cancellata, Sow., Thes. Conch., vol. i. p. 358, pi. Ixxi. figs. 93-95. 

 Terebratulina cancellata, Reeve, Mon. of Terebratiila, Conch. Icon., pi. iv. fig. 13. 

 Terebratulina cancellata, Dall, Cat. of the Recent Species of the Class Brachiopoda, Proc. Phil. Acad. 

 Nat. Sciences, p. 179, 1873. 



Shell rather large, elongated oval or ovate, livid brown or yellowish, with darker 

 concentric bands, widest about the middle, nearly straight in front. Dorsal valve very 

 convex, flattened longitudinally along the middle, from which the lateral portions slope 

 away at a rapid angle. Ventral valve convex rather less deep than the opposite one, and 

 sometimes flattened towards the front. Beak incurved tapering, moderately produced 

 and truncated by a rather large foramen which is very slightly separated from the hinge- 

 line by a very narrow deltidium, the beak often slightly overlying the umbo of the 

 dorsal valve. Surface of both valves ornamented with a very great number of delicate 

 raised striae or ribs, augmented in number at various distances from the beaks by the 



