1898.] MICROSCOPICAL JOURNAL. 201 



to make sections of valuable museum specimens ot recent 

 and fossil woods. Mr. Robertson has found that by di- 

 rectly photographing- the surface by means of a micro- 

 photog-raphic apparatus, excellent pictures, giving- all 

 necessary histolog-ical details of the tissues can readily be 

 obtained. The recent wood surfaces are planed with a 

 steel plane, and if at all roug-h the surface is wet. 

 Very careful focussing is necessary, so as to get equal il- 

 lumination. An opaque focussing- plate should be ased for 

 roug-h adjustment, but the final focussing must be done 

 with a clear glass plate. The illumination was by means 

 of a magnesium ribbon fed throug-h a fixed tube and 

 placed at an ang-le of 45 degrees and a distance of ten or 

 twelve inches from the surface to be photog-raphed. An ex- 

 posure of about forty seconds with Ilford plates g-ave the 

 best results. — Science Gossip. 



Quick Method of Preparing Sections. — It is often desir- 

 able to prepare sections of soft tissues in a very short 

 time. To those who are familliar with the collodion 

 method the following- sug-g-estions by Mr. M. P, Thomas 

 in the "Journal of Appeal Microscopy" will be helpful. 

 Place the tissue at night in forty per cent alcohol in the 

 dehydrating- apparatus. Remove it at 7.30 the next morn- 

 ing-. Leave until 10 o'clock in two per cent collodion. 

 Then place in five per cent collodion until 11.45, Arrang-e 

 on the cork and place in eig-hty per cent alcohol. The 

 material will be ready to section at 1.30. A total of 

 eig-hteen to nineteen hours covers the whole operation. 



Nematodes for Microtome Sections. — The following- 

 methods of preparing- nematodes for sectioning- with the 

 microtome has been used by Dr. Kaiser with much suc- 

 cess. The main difficulty to be overcome is the curling- 

 up while being- killed. To prevent this place the worm on 

 a slide with a few drops of water. Over it place another 

 slide and move it slowly to and fro. This movement 

 causes the worm to straighten. As soon as the nematode 

 assumes the desired position the fixing- liquid is pipetted 

 between the slides, the motion of the upper slide being- 

 continued until the worm is dead. By this method one can 



