HYMENIACIDON. 91 



" Examined. — In the dried state. 



*' I received from my friend the Rev. A. M. Norman 

 five specimens of this iijsignificant-looking sponge j 

 two of them from Westport Bay -were so embedded in 

 the cavities of small rough and rugged fragments of 

 portions of a basaltic rock as to be quite unfit for 

 dehneation ; another broken specimen was embedded 

 amid small fragments of NulUjpora polymorpha from 

 Birterbuy Bay. Some of these specimens exhibited the 

 oscula well ; they were small and simple and irregularly 

 dispersed -, none of them exceeded a line in diameter. 

 The remaining two specimens are those represented 

 in Plate XV; figs. 1 and 2. The one represented by 

 Pig. 1 was dredged by Mr. Norman in Birterbuy Bay. 

 The sponge is on the margin of a fragment of an 

 old bivalve shell which on its other side has several 

 smaU specimens of Isodictya MacAndrewii. The speci- 

 men represented by Pig. 2 was presented by Mr. 

 Eobertson to Mr. Norman, to whom he stated that 

 it was collected by the late Dr. Scouler, but from what 

 locality was unknown. This specimen also is on a 

 fragment of an old shell. It is exceedingly like the 

 type represented by Fig. 1 both in its external and 

 anatomical structures ; several oscula in a closed con- 

 dition are apparent on this specimen by the aid of a 

 lens of two inches' focus. 



" Bach of the figured specimens consists of a small 

 dull-brown patch of an irregular form about three- 

 fourths of an inch in diameter, and not exceeding an 

 eighth of an inch in thickness. Its anatomical struc- 

 ture is exceedingly simple. Its spicula are all of nearly 

 the same size and form, but varying to a slight extent 

 in their diameter ; and if it were not for their unusual 



