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2Ó2. H. Stat. 319. 6° 16.5 S., 114 37' E., 82 Metres; fine yellowish grey mud (on 282. B., 

 Stichoporina simplex). 



Size large, reaching a total length of about 2.85 mm. Stalk interrupted by two or three 

 muscular joints, the intervening parts covered by a well developed cuticle, which is smooth or 

 has only the barest traces of tubercles. These internodes are cylindrical in form, expanding as 

 they reach the joints. Tentacles probably not less than 20 — 24. 



I am unable to refer this species to any of the forms of Barentsia previously known. 

 In general appearance it has considerable resemblance to the jointed forms of B. discrcta 

 described by Waters l ) from Ile Londonderry, Chili. Waters gives Pedicellina australis Jullien 

 {11011 Ridlev) as a synonym of B. discrcta ; and a reference to Jullien's account') shows that 

 in the form described by that author the stalk may be jointed. It is not impossible that the 

 specimens here described may be identical with Jullien's species, although> it appears improbable 

 that they are jointed forms of B. discrcta, since the pores so characteristic of the stalk of that 

 species are not present. 



The muscular base of the stalk is divided from the next part by a chitinous diaphragm. 

 Waters has described a similar arrangement in his Chilian specimens; but in those which I 

 have referred to B. discrcta the diaphragm is usually not present, or is represented (in Japanese 

 specimens) by a slight annular thickening of the cuticle, which hardly projects into the cavity 

 of the stalk. 



A similar diaphragm occurs on the distal side of each of the stem-joints; and, as Waters 

 has suggested, it perhaps serves for the insertion of the longitudinal muscles of the basal 

 dilatation and of the joints. Evidence of the insertion of muscles into a diaphragm has been 

 alluded to in the description of B. discrcta (see p. 31). 



The following are the lengths, in u, of the several parts of the individual shown in 

 fig. 6: — basal dilatation, 250 ; first internode of stalk, from the proximal diaphragm to the 

 commencement of the joint, 860 ; first joint, to its distal diaphragm, 150; second internode oi 

 stalk, 5 80; second joint, 130; third internode, 270; calyx, 400 ; total, 2640. The breadth of 

 the calyx is 310 p.. 



I am not able to state the number of the tentacles with certainty, but it appears to be 

 about 24. The specimen figured seems to be a female, with an embryo in its brood-pouch. 



The stem-internodes of this species are much longer than those of B. (Arthropodaria) 

 benedeni Foettinger. They more nearly resemble those of a specimen referred by Ritchie s ) to 

 B. gracilis, which is, however, a much smaller species than the one here described. The length 

 (in the figure) of the longest individual shown by Ritchie in fig. 5 is about 115 mm. As the 

 figure is said to be X l 4°, this gives a total absolute length of less than 1 mm. 



1) Waters, A. W., 1904, p. 99, PI. VII, figs 60, 6</. 



2) Jullien, J., 188S, p. 13, PI. VIII, fig. 4. 



3) RITCHIE, J., 191 1, Trans. R. Soc. Edinburgh, XLVII, Pt 4, p. S41. 



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