536 



demanded the exact appearance seen on looking down the tube^ 

 but enabled him to obtain very fair determinations of the wave- 

 lengths of red, green and violet light from the dots of Fleurosigma 

 formosum, and from the divisions of a stage micrometer. As a 

 matter of fact, Abbe bad described thirty years ago very care- 

 ful experiments made by him to prove that refraction could not 

 explain the behaviour of microscopical objects. Refraction might, 

 however, considerably alter the relative brightness of the diffrac- 

 tion-spectra, but without affecting their position. 



The following objects were exhibited : Larva of Stratiomys 

 chamaelion, by Mr. E. E. Banham ; corneal epithelium, showing 

 variously shaped cells, by Mr. J. T. Holder ; a specimen of the 

 beautiful diatom, Bacteriastrum sp., from the Challenger collec- 

 tions, by Mr. A. Morley Jones. 



At the meeting of the Club held on June 25th, 1912, Prof. 

 Arthur Dendy, D.Sc, F.R.S., President, in the chair, the 

 minutes of the preceding meeting, held on May 28th, were read 

 and confirmed. 



Messrs. J. Gurney, W. N. Jaquin, G. F. W. Howorth, G. F. 

 Hook and J. C. Morris were balloted for and duly elected 

 members of the Club. 



The list of donations to the Club was read and the thanks of 

 the members voted to the donors. 



The Hon. Sec. said that Mr. F. Whitteron, of Geelong, who 

 was present as a visitor, had brought a number of specimens of 

 a rare Holothurian, Trochodota dunedinensis, for distribution to 

 members who wished to examine it. 



The President said the Club was exceedingly fortunate in 

 having such a gift. It happened that this organism had peculiar^ 

 interest to him. He knew Geelong well, and had done a good 

 deal of dredging in Port Phillip, but T. danedinensis came 

 not from Geelong, but from New Zealand, and w^as named 

 after the city of Dunedin by Prof. Parker. He had collected it 

 at Dunedin, and had written an account, with figures, which 

 appeared in the Zoological Journal of the Linnean Society some 

 twelve to fifteen years ago. It has a variety of shapes of spicules, 

 and in particular some of a special wheel-like form. He had 

 been fortunate enough to work out the development of these 



