BY W. M. BALE. 783 



the length of the hydrotheca, terminating below in a slight 

 rounded enlargement, and above in a similar but larger extension 

 at the end of the hydrotheca. The supracalycine sarcothecae are 

 set behind the upper part of the hydrotheca, so that in a front 

 view they can only be seen by focussing down through it. The 

 possession by this species of a distinct intrathecal ridge, anterior 

 in position, is a feature which, though common among the 

 Australian Statoplea, has not hitherto been recorded as occurring 

 in any member of the Eleutheroplean group, except in a single 

 doubtful species, Azygoplon jiroduGtum,; the true Plumulariee which 

 are furnished with an intrathecal ridge, as P. spinulosa, P. 

 Jllicaulis, (fee, having it in a posterior position. The lateral 

 external webs, which appear to partly shelter the lateral sarco- 

 thecse, are so delicate that they escape observation except on a 

 careful scrutiny. Somewhat similar structures occur in P. 

 filicaulis. 



P. alata was found growing on a red frondose alga, which was 

 given to me by Dr. Ralph, who was uncei-tain whether it had 

 been collected in New Zealand or Victoria. 



Plumularia spinulosa. Bale. 



(Plate XIX., figs. 11-13). 



Coogee Bay (Mr. Whitelegge). 



The gonosome of this species has been hitherto unknown, but 

 Mr. Whitelegge's specimens contain some gonothecje, which are 

 very large, ovate, truncate above, and with the margin rather 

 widely everted. They somewhat resemble those of P. ohliqua, a 

 species which agrees with the present in many respects, especially 

 in the form and arrangement of the sarcothecgo. P. spiiiulona 

 however may be distinguished by the more compressed hydro- 

 tliecso, the large intrathecal ridge, the abrupt narrowing of the 

 pinna Vjehind the calycle, and by the pinna being pointed at the 

 end. The specimens from Coogee differ from those I had previously 

 seen in having the pinna shorter, terminating in a blunt conical 



