AN ENTOPROCTAN POLYZOON (BARENTSIA BENEDENl). 841 



Pedicellina gixicilis, but a two-jointed individual ; for in addition to the swelling at the 

 base, the proportion of which is similar to that in the figures of Calf of Man specimens in 

 this paper (PL I. figs. 6 and 7), there is a second slight swelling some distance below the 

 calyx. This cannot be explained except as a second muscular expansion. Sars' figure 

 closely resembles especially those specimens which I obtained oft' the Calf of Man. One 

 difference is to be noted — that in Sars' representation the calyx is placed symmetrically 

 on the stem, notwithstanding that the indications of the internal organs seem to show 

 that a lateral view is given. Since, however, in his neighbouring figures of Pedicellina 

 echinata (especially lb, id, le), a similar bilateral symmetry is preserved, in spite of the 

 fact that in that species the calyx is "very ventricose on the one side," little importance 

 need be attached to this evident misrepresentation. 



There exists doubt, expressed by van Beneden in first describing Pedicellina belgica, 

 and later by Foettinger, concerning the distinctness of P. gracilis and P. belgica. 

 This doubt is increased by consideration of the resemblances of habit exhibited by the 

 two forms. In each case, the simple one- jointed type of stem, with a single swelling at 

 the base, is the rule. But Hincks has described a form of P. gracilis in which the stem 

 is " very much elongated, and consists of several sections separated by knots or swellings, 

 which are also muscular in character." # This form was given a varietal name by Lomas 

 as P. gracilis var. nodosa,^ and later was raised to specific grade as Gonypodaria 

 nodosa, by Ehlers. A similar relationship between simple and jointed individuals 

 has been described by Hilgendorf in colonies of Pedicellina gracilis from New 



Zealand.^ 



But an identical relationship between two similar forms occurs in colonies of 

 Pedicellina belgica. The examples I have examined were forwarded to me by Professor 

 Foettinger, from Ostend, the locality where van Beneden obtained his type specimens. 

 In the colonies before me there occur on the same stolon single unjointed individuals 

 typical of the habit of P. belgica or P. gracilis, and individuals with from two to four 

 elongated internodes, some of which I am unable to distinguish from P. gracilis var. 

 nodosa (PI. I. fig. 5). Here the two forms are not even distinct " varieties " of P. belgica ; 

 and the observations of Hincks, Lomas, and Hilgendorf, together with this analogy, 

 indicate that a similar relationship unites the two forms of Pedicellina gracilis, and con- 

 sequently that Gonypodaria nodosa as a distinct species does not exist, and that " var. 

 nodosa " is not a variety in any very significant sense. 



Since this note was written, I have had the good fortune to obtain a few specimens 

 of Pedicellina gracilis from the English coast. They were found upon the stem of 

 a hydroid, Antennularia ramosa, which had been dredged by Professor W. A. Herdman's 

 S.Y. Ladybird in the Irish Sea to the north of the Calf of Man, depth about 10 

 fathoms. The specimens are poor in number and in quality. The majority of the 



* Hincks, T., A History of the British Marine Polyzoa, 1880, p. 570. 



t Lomas, J., " Report on the Polyzoa of the L.M.B.C. District," Proc. Lit. Phil. Soc. Liverpool, No. xl., 1886, 

 p 190, pi. iii. fig. 2. 



t Hilgendorf, Trans. New Zealand Inst, vol. xxx., 1897 (1898), p. 218, pi. xxii. 



