204 THE AMERICAN MONTHLY fJul 



Notes on Microscopy. 



F. SHILLINGTON SCALES, F.R.M.S. 



Mounting Botanical Slides. — The best book for the 

 beginner is Cross and Cole's "Modern Microscopy." Pages 

 114 and 144 to 154 deal specifically with the mounting of 

 botanical specimens and are most clear and lucid, as might 

 be expected from a mounter of Mr. Cole's experience. I 

 would also recommend strongly to your notice Strasbur- 

 ger and Hillhouse's "Practical Botany" which, written 

 primarily for the student of botany, contains eminently 

 practical instructions in microscopical technique, and 

 should be mastered by all who are interested in plant life. 



The Malaria Parasite. — Readers can hardly fail to be 

 interested in the recent investigations of Major Ross, into 

 causes and dissemination of malaria ; investigations which 

 appear to have solved the hitherto apparently insoluble 

 problem as to the mode of life of the parasites to which 

 malaria has now been traced, and to have given the final 

 coup de grace to the old theory that it is connected with 

 a certain condition of the soil. It is now placed beyond 

 a doubt that malaria is due, and probably due only, to a 

 parasite belonging to the family Hsemaoebidfe, passing a 

 stage of its existence in the stomach of certain mosqui- 

 toes, and by the bites of the latter infecting the blood of 

 man. The life-history of these parasites has been com- 

 pletely followed by Major Ross in Culex pipiens and con- 

 firmed by others in Anopheles claviger. We would refer 

 those who desire fuller information on this point to a paper 

 by this investigator in "Nature" for August 3rd. The in- 

 terest now lies in the question of the exact species of mos- 

 quito rather than that of the parasite. Major Ross, in 

 more than one report has adduced facts in support of his 

 strong belief that the dissemination of malaria is confin- 

 ed only to the comparatively rare "spotted-winged" mos- 

 quito, belonging to the genus Anopheles, and which has 



