344 DISCOVERY REPORTS 



sorted without magnification. N. vanhoffeni has stouter branches with a more serrated 

 outline due to the difference in shape of the majority of the marginal avicularia (cf. 

 Figs. 9 A-C and 10 A, B). These not only differ in outline but have their mandibular 

 surface tilted more towards the frontal surface of the branch. All this is shown in 

 Kluge's figures. 



i.s. 







•^mm 



Fig. io. A. Notoplites vanhoffeni (Kluge). St. TN 348, McMurdo Sound. One zooecium to show scutum 

 with 'islands'. Part of the ovicell of the proximal zooecium is also shown. B. N. vanhoffeni (Kluge). 

 St. TN 339, Ross Sea. To show branched internal spines and differences in orifice from N. drygalskii 

 (cf. Fig. 9 A). C. N. antarcticus (Waters). St. 39, South Georgia. Ovicell and adjacent structures. 

 The scutum is not normal, cf. normal scutum shown in Fig. 9 D. 



c. cryptocyst, i.s. internal spine, o. ovicell. 



The ovicells of N. vanhoffeni are always sculptured, those of N. drygalskii are usually 

 smooth, but occasionally (e.g. from St. TN 331) there are little papillae on the ento- 

 oecium giving the ovicell a sparsely punctate appearance (Fig. 9 B). 



The frontal avicularia vary in size, and there is some variation in the pattern of the 

 scutum. In N. drygalskii there may be " granulation " as in Kluge's specimens or these 

 markings may be larger and more irregular as in the specimen figured (Fig. 9 A). In 

 either case they appear to be interruptions, "islands " one might call them, in the lumen, 

 not granulations of the surface of the scutum. In N. vanhoffeni the lumen is less ex- 



