CAMPTOPLITES 447 



4. Camptoplites bicorms var. elatior (Kluge). Plate XI, fig. 3 ; Figs. 43 N, 44 D. 



Bitgula bicomis var. elatior Kluge, 1914, p. 622, pi. xxix, fig. 4, text-fig. 9 (not pi. xxix, fig. 3). 

 Station distribution. Antarctic: Weddell Quadrant, Sts. 180, 190, 1948. 



Geographical distribution. Near Elephant Island; Palmer Archipelago (Discovery); Bellings- 

 hausen Sea; Wilhelm II Land (Kluge,); off Oates Land (Terra Nova). 



The varieties of Camptoplites bicomis are compared on p. 443. 



The Discovery material from St. 180 agrees very closely with var. elatior as repre- 

 sented in Kluge's diagnosis and pi. xxix, fig. 4. In the specimens from Sts. 190 and 

 1948 the upper head-angle of the large long-headed avicularium is more obtuse and may 

 measure as much as 150 . 



The ancestrula is described on p. 438 (species 7). 



5. Camptoplites bicornis var. quadriavicularis var.n. Plates X, fig. 3, XII, figs. 



1, 2; Figs. 43 A-G, 44 A, B. 



Station distribution. Sub- Antarctic: South Atlantic Ocean, St. WS 871. Antarctic: Weddell 

 Quadrant, St. 160. 



Geographical distribution. Off Patagonian Shelf, below 300 m. (Discovery; 34. 1 1 . 12 . 10, 85) 1 ; 

 Shag Rocks (Discovery). 



Holotype. St. 160, Shag Rocks. 



Description. Main branches biserial, except at bifurcation where there may be three, 

 or rarely four, series in younger parts of colony, zooecia moderately elongated, tapering 

 fairly uniformly towards proximal end (Fig. 44 A), distal end of zooecium raised, distal 

 corners angular, the inner one sometimes spike-like or bearing a spine. 



Secondary branches biserial, zooecia shorter than those in main branches and tapering 

 more rapidly, distal corners as in main-branch zooecia. 



Runners only present where axillary chamber forms rootlet. 



Ovicell (Fig. 44 B) very shallow and as wide as the zooecium, see pp. 443-444. 



Avicularia exceptionally long-stalked. Round-headed avicularia all of the same shape, 

 but usually of two sizes, larger ones gigantic ; beak long, stout, down-turned ; mandible 

 with knob on each side of distal point (Fig. 43 A, B). Large long-headed avicularia big, 

 with strongly curved beak (Fig. 43 D), upper head-angle 125-135 , stalks often of very 

 great length (may be more than four times as long as a typical main-branch zooecium). 

 Small long-headed avicularia as in other varieties of Camptoplites bicornis except for 

 presence of oblique calcareous thickening separating beak from head (Fig. 43 C), 

 attached to gymnocyst near proximal border of opesia, leaving small scar when detached. 

 Other three kinds attached more proximally leaving large scars (Fig. 44 A). 



Remarks. The type colony is a bushy tuft 2 in. high (Plate X, fig. 3). In its main 

 characters this form agrees with C. bicornis, as understood by Kluge, and is nearest to 

 var. magna from which it differs in the shape of the zooecia, particularly those of the 

 secondary branches, in the presence of the thickening in the head of the small long- 

 headed avicularia, in the great length of the avicularian stalks, and in the presence in 

 most specimens of gigantic round-headed avicularia as well as the smaller ones. 



1 Found among material of other species from Challenger St. 320. 



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