1897] MICROSCOPICAL JOURNAL 29 



teiitioii, is that an object always appears to be in that direc- 

 tion in which the rays of lig-ht last reach the eye. It was, 

 Mr. Allen said, a highly important principle, which was 

 sometimes not so thoroug-hly borne in mind as it should be. 

 Mr. Allen then described the laws of optics utilised in the 

 construction of the microscope, illustreiting- his observa- 

 tions by numerous demonstrations carried out by means 

 of a beam of lig-ht. He also explained the mag^nifying- 

 power of different object glasses and eye-pieces, and dealt 

 in a chatty but interesting and instructive way with other 

 details connected with the optical construction of the mi- 

 croscope. 



Liverpool Microscopial Society. 



"The Microscopic Study of Cotton and other Fibres," 

 was the subject which Mr. F. H. Tate, F.C.S., discussed 

 before the members of the Society recently. The paper 

 dealt principally with cotton, and described the structure, 

 mode of growth and development of the fibres. The dif- 

 ferent structures of the plant were exhibited by lantern 

 illustrations and their several chai'acteristics were ex- 

 plained. Micro-photography was relied upon to reveal the 

 difference between healthy and diseased fibres. The 

 fibres of other materials, as wool, silk, flax, etc., were simi- 

 larly described and exhibited. 



Quekett Microscopical Club. 

 The 346th ordinary meeting of this club was held on 

 Friday, Nov. 20th, at 20, Hanover-square, Mr. J. G. Wal- 

 ler, president, in the chair. Mr. T. Rosseter, F.R.M.S., 

 read a paper on a new Cysticercus and Teenia. The for- 

 mer infests the entomostracan, Cypris fusca, and the ma- 

 ture tapeworm develops in the common duck. Mr. Ros- 

 seter gave a most interesting- account of his experiments 

 in feeding the birds with the entomostraca, his frequent 

 failures, and final success. The paper was illustrated by 

 drawings of the various stages and details of structure, as 

 well as by diagrams on the board. In moving a vote of 

 thanks, the president remarked that Mr. Rosseter ap- 

 peared to be the sole investigator of these parasites, so far 



