1882.] 



MICKOSCOPICAL JOURNAL. 



179 



in a mixture of spermaceti and castor oil, 

 and sections were cut. In this way speci- 

 mens were obtained with " absolutely no 

 shrinking of the protoplasm." 



— Mr. G. Stocker finds that a strong 

 solution of potash-alum in water, will pre- 

 serve the coloring matter of patts of 

 plants. The pieces are placed in the 

 solution for about ten minutes, then dried 

 between pieces of blotting-paper, and 

 passed through turpentine into balsam. 



— Some time ago it was announced 

 that certain insect-pests had been killed 

 by the application of yeast, which acted 

 as a parasite to destroy them. Later ex- 

 periments have in some cases succeeded, 

 and failed in others. It has been suggested 

 that the yeast-plant itself is innocuous, 

 but there might have been a parasite 

 associated with it, which proved fatal to 

 the insects. This idea seems not to be 

 borne out by the observed facts. Prof. 

 Hagen now believes that the yeast-plant 

 must be in a certain stage of growth in 

 order to prove effective, and he thus ex- 

 plains the failure of some of the experi- 

 ments. 



— Mr. W. P. Collins, of London, who 

 probably has the best collection of old and 

 new books treating of microscopical sub- 

 jects to be found in any book-store, will 

 send a copy of his new catalogue to any 

 applicant. The June catalogue adver- 

 tises a large number of valuable second- 

 hand publications, and full sets of micro- 

 scopical periodicals. 



— There is a good article in the March 

 number of the Journal of the Quekett 

 Microscopical Club by W. H. Gilburt, 

 F.R.M.S., " On the Structure and Division 

 of the Vegetable Cell." The subject is 

 treated very clearly, and, while it is quite 

 elementary, it will doubtless be instructive 

 to many beginners in microscopic study. 

 The author, h'^wever, in our opinion, 

 places too much confidence in the de- 

 clarations of Flemming and Klein regard- 

 ing the structure of nuclei, for it is still 

 doubtful if their obser^ations of the net- 

 work of the " chromatin " are to be ac- 

 cepted as correct. There are good rea- 

 sons for taking them cum grano salis. 



— Dr. L. Brewer Hall has described a 

 form of eye-protector for use with the mi- 

 croscope, which he thinks possesses some 

 advantages over others. He describes it 

 as follows : " The form that I now pro- 



pose consists of a small, opaque disk near 

 the eye, supported by a wire extending 

 from its outer edge downward to a point 

 on the tube low enough to be out of the 

 way of the nose, then bent upward, par- 

 allel to the tube but not touching it, and 

 attached to a ring near the top. I made 

 mine of a piece of brass wire. No. 18, 

 about 45 centimetres long; a loop at one 

 end 4 centimetres in diameter, covered 

 with a piece of black paper folded over 

 and gummed down, forms the disk. At 

 the other end, I made a ring to fit the 

 draw-tube, and then bent the intermedi- 

 ate wire. I attach mine below the flange, 

 on the draw tube, where there is no lac- 

 quer to be scratched, but if it should be 

 thought desirable to attach it above the 

 flange then the ring ought to be covered 

 with chamois, so as not to wear the polish." 



— There is a very interesting article in 

 the April number of the Northern Micro- 

 scopist about " The Cypris and its Fossil 

 Ancestors" by R. T. Burnett, F. G. S. 

 Beginning with a short description of 

 this minute entomostracan the author re- 

 fers to its almost universal distribution in 

 rivers, lakes, salt marshes and in the seas, 

 and mentions the deposits of sand and 

 clays about the great lakes in which fossil 

 shells of species that are now living are 

 found. Then follows a summary of the 

 work of the " Challenger" expedition 

 with reference to this subject. Cypris 

 has been found in the globigerina ooze of 

 the Atlantic at a depth of 1,452 fathoms. 

 From twenty-nine dredgings, at depths 

 greater than 500 fathoms, fifty-two 

 species were found. At great depths 

 the species are much less numerous. The 

 fossil ancestors of the cypris can be traced 

 back as far as the oldest stratified rocks — 

 being found in the Laurentian and Cam- 

 brian formations — with occasionally a 

 break in the continuity. The ostracoda 

 were most abundant during the mesozoic 

 just preceding the cretaceous, where they 

 were about as numerous as they are at 

 the present time. For a satisfactory re- 

 sumd of this subject, the reader is referred 

 to the original article. 



— The fifth fascicle of the " Synopsis 

 of Diatoms " is now in the hands of sub- 

 scribers. It contains twenty-six plates, 

 with 449 figures. The total number of 

 plates now issued is 104, containing 2,658 

 figures. The sixth fascicle, which will com- 

 plete the work, will be out in a few 

 months. 



