680 NOTES AND EXHIBITS. 



NOTES AND EXHIBITS, 



Mr. Whitelegge exhibited specimens of Porina inversa, a species 

 of Polyzoa from Port Jackson, and in reference to them read the 

 following note — "Mr. Waters has recently described a new- 

 species of Polyzoa from Port Jackson, under the above name (Ann. 

 Mag. Nat. Hist., Sept. 1887, p. 190), concerning which he says, 

 that the shape of the oral aperture is the reverse of the usual shape 

 of Porina, and, in fact, of the Bryozoa generally. After examining 

 a large number of specimens of this species, it is my opinion 

 that the aperture does not differ in shape but in position. It 

 is the aperture which is reversed, as the following details will 

 show. On viewing a specimen from its frontal aspect the oper- 

 culum may be seen in various positions, from closed to fully 

 open, and in every case the oral aperture, when it can be seen 

 at all, is situated between the front of the cell and the oper- 

 culum ; the latter is hinged on to the distal border of the aperture, 

 and, when fully open, the outer surface is in contact with the base 

 of the next cell above, whilst the inner faces towards the front, so 

 that the free edge of the operculum rests on the proximal, and the 

 straight edge is attached to the distal, margin of the cell. This 

 reversed aperture evidently escaped the notice of Mr. Waters, when 

 he penned his description. The importance of such a deviation 

 from the usual structui-e of the class induces me to take an early 

 opportunity of calling the attention of students of Polyzoa to the 

 fact. In conclusion, I may say that fortunately the species is very 

 common in Port Jackson." 



Dr. Katz exhibited pure cultures of the phosphorescent bacteria 

 mentioned in his paper, and he said that he would be glad to 

 receive samples of luminous sea-water, or luuiinous meat, from any 

 members who might chance to meet with them. 



