BRACHIOPODA JACKSON. 19.", 



absence of dental plates is alsn mil indicated. [Sec Dall, 18!).">, pp. 717-8, pi. -'31, 

 figs. ;")-(;]. 



[n all probability the Hemithyris sp., dredged in 1,410 fathoms, off Coats Land, 

 . \iitarni, -I, I iy the "Scotia" Expedition [Jackson, 191:2] is referable to ( 'oiiijixnf/it/rix 

 ninirif:,!', but tlie imperfect nature of the material renders a decision on this point out 

 nl the question. The mosaic formed by the prisms of the test is apparenllv larger. 



The presence in 6V//'Mi//////-/.v i;i,;irit~ii' and /'V/V/c/W Imlli of features characteristic 

 ot Palaeozoic genera of the Rhynchonellidse is particularlv noteworthy. As in 

 Camarotcechia, the apex of the ventral valve is encroached upon and cut into liy the 

 elliptical foramen, though the deltidial plates in Compsothyris and Friili'iii are never 

 completely united so as to close the lower part of the aperture. Somewhat similar 

 conditions are also present in ltli>/nrli<>tr,'t<i. In like manner the intimate connexion in 

 Compsothyris &n& /''/!: /<'!</ n\' the mesial septum of the dorsal valve with (lie hinge- 

 processes recalls Camarotcechia, in which the crural lamina.- are united liy a deposit of 

 callus to a cup-like expansion of the septum. In ('. r<i<;>rit;<t> this feature is equivalent 

 to the part marked " d " (rostral chamber) in fig. 591C'. of < '<niittrf<i-r/i/n i-m/i/ri'i/itfn 

 (Conrad) figured by Sclmchert in Zittel [1913, p. 397]. 



S. L!nf/ii/ir//ii iiiifuri-fica (Blochmann, 190H). 



Liiitlti/rinii iiiilnrt-ticn, Blochmann, Zool. Anzeiger, Bd. xxx, 1906, p. 692. 



Blochmann, Zeitschr. f. wiss. Zool., Bd. 90, 1908, p. 614. 



Blochmann : Eichler, " Die Brack der Deutsch. S.-P. Exped., 1901-03," 

 xii, Zool. iv, 1911, p. 89, pi. 42, figs. 1-4 pi. 43, figs. 13, 19, 20; pi. 44, tigs. 25-34. 



/A/A. Stations 220 '., 294, 314, 316, 338, 339, 340, 355, 356 ; 50-300 fathoms. 



( >/>*. In some of the above stations this species occurred in fair numbers (Station 

 355 the deepest -yielded some eighty or ninety specimens), but in others only one 

 or two examples were dredged. 



Many of the shells obtained are in a dead condition. Several have been bored by 

 carnivorous gastropods, and one or two have the outer layer of the shell undermined, 

 as in Compsothyris ri(cnvit;n'. Some of the examples, from Stations 316, 338, and 355 

 especially, are studded with the tests of Foramiuifera, resembling Discorbina, and most 

 of the living examples are attached to fragments of Polyzoa. In one or two cases 

 individuals show irregularities of growth due to accident. 



The abundance of individuals, in some cases, seems to be an indication of favourable 

 conditions for existence. 



The dimensions of the specimens are, in general, larger than those obtained from 

 the type station in the Eastern Antarctic. Some of the largest, from Station 355, are 

 detailed below : 



Length, in mm. 

 Width 

 Thickness ., 



