= 5 



Another species which may be noticed in the present connexion is P. breusingi, 

 described by Studer x ) from Kerguelen ld, zone of Florideae. This species is said to differ from 

 P. australis Ridley, in the number of its tentacles (16 — 18), in the irregular form of its stolon, 

 in the absence of diaphragms in the stolon, and in the shape of the calyces. It may be sur- 

 mised that the supposed absence of diaphragms was due to a mistake in the observation, 

 since it is not in agreement with what is known of other Pedicellinidae. 



Barentsia Hincks. 



Barentsia Hincks, 1S80, "Hydr. and Pol. Barents Sea", Ann. Mag. Nat. Hist. (5) VI, p. 285. 

 Ascopodaria Busk, 1886, 'Challenger' Rep., Pt. 50, p. 41. 



Artliropodaria Ehlers, 1890, "Z. Kenntniss d. Pedicellineen", Abh. Göttingen, XXXVI, p. 144. 

 Gonypodaria Ehlers, 1890, t. cit., p. 144. 



The Genus Barentsia, characterized by having a muscular enlargement at the proximal 

 end of its stalk, was established by Hixcks in 1SS0 for a new species, B. bulbosa ~), from 

 Barents Sea. This species differs from most of the forms which have subsequently been added 

 to the genus in the fact that the stalk gives rise laterally to new stalks-, a feature which is 

 also shown by B. variarticulaia Andersson s ) and by Gonypodaria ramosa Robertson 4 ). In 

 1SS4 Hincks 5 ) instituted a new genus, Pedicellinopsis; but he subsequently") expressed the 

 opinion that it was synonymous with Barentsia. In 18S6 Busk defined the genus Aseopodaria, 

 admiting its identity with Barentsia, but justifying his use of the name partly on the ground 

 that he had used it as a IMS. name in 1879, and that it had been mentioned in that year 

 by Allmax. Allmax's reference to the genus is, however, unaccompanied by any diagnosis, 

 so that Ascopodaria was a nomen nudiun when HlNCKS described Barentsia. In 1890 Ehlers 

 introduced the two genera Artliropodaria and Gonypodaria, the former characterised by its 

 jointed stalk. 



The genera thus described have been criticised by various authors. Ritchie '), in a 

 recent paper, has given reasons for regarding Artliropodaria and Gonypodaria s ) as synonyms 

 of Barentsia, on the ground of the variation, in the characters which have been used to 

 distinguish those genera, observable within the limits of a single species ; and he suggests that 

 any species of Barentsia can probably give rise to a joint in its stalk. This is perhaps going 

 bevond the evidence, since jointing has not been described in by any means all the species. 



But that the stalk can become jointed in certain cases is clearly shown by many 

 observations, including his own here referred to. In two species the faculty of forming joints 



1) Studer, T., 1S89, "Forschungsreise •Gazelle'", III. Theil, Zool. i; Geol., p. 140. 



2) See also the descripticn, 1 by \V. J. VIGELIUS, 1S84. of the same species in "Die Bryozoen 'Willem Barents 1 '', Bijdr. tot de 

 Dierkunde, XI, p. 85, figs on PI. VIII. 



3) Andersson, K. A., 1902, "Bry. schwed. Exp.", Zool. Jahrb. Syst. XVI, p. 557. It seems doubtful whether this species is 

 really distinct from B. bttlbosa. 



4) Robertson, A., 1900, "Stud. Pacific Coast Entoprocta", Proc. Cal. Acad. Sci. (3) Zool. II, X° 4, p. 337. 



5) Hincks, T.. 1SS4. "Contr. Gen. Hist. Mar. Pol.", XIII, Ann. Mag. Xat. Hist. (5) XIII, p. 364. 



6) Ibid., 1893, Appendix, Ann. Mag. Xat. Hist. (6) XII, p. 140. 



7) Ritchie, J., 1911, "On an Entoproctan Polyzoon . .", Trans. R. Soc. Edinburgh, XLVII, Pt 4, p. 840. 



8) Waters (1904, "Rés. Voy. Belgica", "l'.rv.", p. 100) had previously expressed this opinion with regard to Gonypodaria. 



2 5 



SIBOGA-EXPEDITIE XXVIII a. 4 



