368 PROCEEDINGS OF THE 



wMle many of the loricate rotifers which haunt the weed were 

 also present. For the examination of a gathering Petri dishes 

 4 in. or 5 in. in diameter and 3/4:th in. deep are convenient. 

 They are placed on a glass plate supported about 3 in. above 

 the table, underneath which is a concave mirror that can be 

 tilted to give dark-ground illumination for the hand magnifier. 

 The Petri dishes may be used on the stage of a microscope in 

 a vertical position when small forms are to be picked out. 

 Rotifers may be picked out with a pipette which should not 

 be too fine even for small forms and males. In the case of the 

 males, which move quickly, it is best to isolate them in a watch- 

 glass, and then get them into a drop of clean water on a slip. 

 This drop may be reduced, and when small enough the cover should 

 be put on with three pellets of wax as supports, which may be 

 pressed down as much as required. Cavity slips are also useful, 

 and flat tinfoil cells such as Mr. Bryce uses. For identifying roti- 

 fers, the most useful book is the German Silsswasser Fauna ; 

 there is also Hudson and Gosse, and a bibliography may be found 

 in the Synopsis of Harring, giving references to various papers 

 in the Q.M.C. and R.M.S. Journals, etc. Mr. Maxwell follows 

 the Rousselet method of mounting, and finds it gives excellent 

 results. Rarities are not too uncommon for the persistent " 

 rotifer hunter, and he thinks the difficulty of handling the 

 specimens is the reason that there is still so much to be discovered. 

 Males, which are comparatively rare, should always be looked for. 

 In some species the male only seeks the female when she is just 

 hatching out, so that the speculative amateur may find interest 

 in the habits and customs of a race of creatures who relegate all 

 their matrimonial problems, whenever these rare events occur, 

 to the nursery, and apply themselves to the serious study of vortex 

 motion and hydrodynamics, and, most earnestly of all, to 

 gastronomies, while occasionally specialising in architecture. 

 Besides aU the normal healthy forms there will at times be found 

 specimens afiected with parasites which are of interest. With the 

 aid of lantern slides Mr. Maxwell then described the various types 

 of rotifers and explained some of the chief points in their structure. 

 Mr. E. K. Maxwell received a very hearty vote of thanks for his 

 stimulating and interesting account of the rotifer- hunter's methods 

 of work. 



A paper by D. Bryce : " On Some Rotifera from Spitsbergen," 



