480 



also for the instruments under which they were shown. Such an 

 ass cniblage — some twenty-five or so — of that rapidly disappearing 

 instrument the binocular microscope as was presented that even- 

 ing is nowadays seldom to be seen ; and as the specimens were of 

 such a nature that they could not be seen to best advantage under 

 any other form of instrument, Mr. Earland said his thanks were 

 all the more due to Mr. Charles Curties for the courtesy with 

 which be had assisted in the provision of so many of the instru- 

 ments used. Thanks were also clue to other friends who had 

 assisted by setting up the specimens exhibited. The majority of 

 the objects on exhibition were selected from the speaker's own 

 dredffingrs taken in the North Sea and North Atlantic during the 

 last year or two, and they were all chosen with the view to 

 illustrating the great diversity of structure and technical skill 

 ■exhibited by Arenaceous Foraminifera — that is, by the forams 

 which have composite tests or shells. Many of the specimens 

 had already been exhibited at the Club on different occasions 

 following their finding ; but as the majority were objects such as 

 were not to be seen every day by microscopists unless specialists 

 in this branch, it was thought that the preparations would all 

 bear a second examination. 



For the benefit of those present who might have but a limited 

 •acquaintance with the order, the lecturer made a few general 

 remarks dealing with the subject. He said that the Foraminifera 

 are very generally divided into three groups, distinguishable by 

 the appearance and structure of their shell-wall. The three 

 groups are : the Imperforate or Porcellanous, the Arenaceous or 

 Composite, and the Perforate or Hyaline. Of these, the first 

 corresponds to the family Miliolidae of Brady — this being the 

 classification generally accepted. The second corresponds, on the 

 whole, with the families Astrorhizidae and Lituolidae of Brady ; 

 and the third, the Perforate or Hyaline group, includes all other 

 forms — i.e. the families Textularidae, Chilostomellidae, Lagenidae, 

 Globigerinidae, Potalidae, and Nummulinidae. It may be men- 

 tioned that, while the Arenaceous group corresponds, on the 

 whole, with Brady's two families Astrorhizidae and Lituolidae, 

 there are certain members of both the other divisions which 

 assume an arenaceous test. These, however, are exceptional 

 species, and for purposes of general classification may be dis- 

 regarded. 



