NOTOPLITES 34i 



9. Basal avicularia absent, distal border of aperture of fertile zooecium smooth 5. N. elongatus 

 Axillary basal avicularia present, distal border of aperture of fertile zooecium beaded 



6. N. elongatus var. calveti 



I. Notoplites antarcticus (Waters). Figs. 9 D, 10 C, 11 B. 



Scrupocellaria antarctica (part) Waters, 1904, p. 25, pi. i, fig. 5 a-e. 

 Scrupocellaria antarctica Kluge, 1914, p. 606, pi. xxviii, fig. 1. 

 Notoplites antarcticus Harmer, 1923, p. 352. 



Station distribution. Antarctic: Weddell Quadrant, Sts. 39, 42, 148, 158, 160, 181, 187, 1948, 

 WS42. 



Geographical distribution. South Georgia (Shackleton-Rowett Expedition ; Discovery) ; Shag 

 Rocks; near Elephant Island; Palmer Archipelago (Discovery); Bellingshausen Sea (Waters); 

 Wilhelm II Land (Kluge); Oates Land (Terra Nova). 



Kluge shows smooth ovicells in Notoplites antarcticus, but in these specimens, which 

 otherwise agree very closely with his restricted definition, the ovicells are sculptured as 

 in Waters 's figure. The sculpture is chiefly peripheral, and particularly lateral, and con- 

 sists of papillae on the outer surface of the entooecium, and less numerous lumps and 

 projections on the inner surface of the ectooecium, some of the projections from the two 

 surfaces being opposite and meeting tip to tip (Fig. 10 C). There are also small thin 

 patches in the ectooecium. The "gefelderte" sculpture of the ovicell of iV. watersi 

 consists of larger and more numerous, but otherwise similar, thin areas in the ectooecium, 

 internal sculpture being only very slightly developed. The ovicell of N. antarcticus is 

 shorter and more prominent than that of N. watersi. Internal spines are developed in 

 the zooecia (see p. 339). 



The scutum is rather variable within the colony, and, despite Kluge's statement that 

 the proximal lobe is rounded, may be quite pointed in otherwise typical specimens. In 

 part of the material from St. 1948 the proximal lobe is pointed and strongly curved, its 

 tip overlapping the inner lateral edge of the opesia (Fig. 9 D). In these specimens some 

 of the frontal avicularia are small and directed frontally as in the figure ; others are 

 typical. Zooecia with two distal spines are also not uncommon in this material, some- 

 times on zooecia with no marginal avicularium, as noticed by Kluge, but also on zooecia 

 that have the avicularium. 



Five ancestrulae, believed to belong to this species, have been found in the 

 Discovery collection, from St. WS 42, 7 January 1927 ; St. 1948, 4 January 1937 ; St. 187, 

 18 March 1927. They are erect and vase-shaped (Fig. 11 B); the attachment is almost 

 tubular; the opesia is distal and oblique; two zooecia are budded from the distal end 

 of the ancestrula and no joint is formed. The first zooecium has a scutum, a small 

 marginal avicularium and two or three spines, and sometimes a small frontal avi- 

 cularium, directed frontally. Where unbroken the scutum of the first zooecium has the 

 form characteristic of the species. The rest of the zooecia successively approach more 

 nearly to the typical specific form, but the larger frontal avicularia, leaning towards the 

 neighbouring zooecium, evidently do not appear till a fairly late stage. The largest of 



