28 " ENDEAVOUR " SCIENTIFIC RESULTS. 



thin out and disappear. Tlie back is smooth or with a few 

 irregular lines, or sometimes so closely fitted against the branch 

 above it tbat the perisarc takes the exact print of the hydrotheca 

 at the back. 



Loc. — Hunter group, 15 fathoms; Great Australian Bight, 

 40 to 100 fathoms. 



Family PLUMULAKIID^E. 



Gknus Plumulakia, Lamarck (in part). 



Pmjmclaria buskii, Bale. 



Plumularia Buskii, Bale, Cat. Austr, Hyd. Zooph., 1884, p. 125, 

 pi. x., fig. 3, pi. xix., tigs. 34 — 35; Trans, and Proc. Roy. 

 Soc. Vict., xxiii., 1887, pp. 94, 108. Hartlaub, Zool. 

 Jahrb., xiv., 1901 , p. 374, pi. xxii., figs. 22, 32, 30. Ritchie, 

 Proc. Zool. Soc, 1910, p. 832. Thorncly, Rept. to the 

 Govt, of Ceylon on the Pearl Oyster Fisheries of the Gulf 

 of Manaar, Suppl. Rept. viii., 1904, p. 120. 



Several specimens of this species were obtained, which do not 

 differ in any important particular from those already described, 

 and on some of them the characteristic female gonangia were 

 present. I have formerly described these as three-sided, with 

 one wide and two narrow sides, the edges being rounded, but it 

 would perhaps be more correct to describe them as having a 

 turgid dorsum and a more flattened ventral surface. The 

 longitudinal ridge of the dorsum often rises higher at the summit 

 of the gonangium than does the opposite side. The two series of 

 large moveable sarcothecse which run up the dorsal surface are 

 somewhat irregularly arranged ; they generally number five or 

 six in each series, with a single one near the top and in the 

 central line. 



The similarity of the gonangia to those of P. obconica, 

 Kirehenpauer (in which however there are said to be at most 

 about half as many sarcotheeae), led me to ask Dr. Hartlaub to 

 compare a specimen with Kirchenpauer's types, Avhich he has 

 very kindly done. He found the types insufficiently preserved to 

 admit of certain identification, but he was able to satisfy himself 

 that if not actually identical with /'. buskii they bore an 

 exceedingly close resemblance to it, notwithstanding the difference 

 of Kirchenpauer's figures, The plicate condition of the 

 hydrotheca' noted by that observer is almost certainly the mere 

 effeel of diying, and the sarcothecre agree with those of P. buskii, 

 and not with Kirchenpauer's figures. The small sarcotheca 

 behind the hydrotheca was not distinguishable, but this may 

 have been due to the bad state of the specimens. 



