XX CONTENTS. 



PAGE 



Conjugation of Swarmspores of Chroolepus No. 5 601 



Structure and Mode of Beproduction of Cutler iacex .. .. „ 605 



New Pai-asitic Alga „ 606 



Siphonocladaccm, a New Group of Green Algm „ 606 



Besting Condition of Vaucheria geminata „ 607 



Italian Algce „ 607 



Suhalpine Desmidiece „ 607 



Algce from Lake Nyassa, (3 figs.) „ 608 



Thallus of the Diatomacem „ 608 



Systematic Position of the Volvocinem „ 609 



Power of Algce to resist Cold No. 6 761 



Marine Algce of the Gulf of Naples „ 762 



New Diatoms „ 762 



Terrestrial Diatoms „ 762 



Formation of the Siphons and Tetraspores in Pohjsiphonia No. 7 932 



Fertilization of Red Algce by the Agency of Infusoria . . „ 932 

 Cell-structure of Griffithsia setacea, and Development of its 



Antheridia and Tetraspores ,, 934 



Reproduction of Cutleria ,, 934 



Conjugation of Ectocarpus „ 935 



American (Edogoniacece „ 935 



New Genus of Chroolepidce „ 936 



Fossil Algce belonging to the Verticillate Siphonece .. .. „ 936 



Influence of Light on the Movements of Desmids ,. ,, „ 937 



New Diatom „ 937 



Adulteration of Currant Jelly ivith Diatoms „ 938 



Palmelline, the Colouring-matter of Palmella cruenta . . „ 938 



Mycoidea parasitica, a new Parasitic Alga „ 938 



Two new Parasitic Algce „ 939 



Method of Cultivating Vohox globator „ 939 



MICKOSCOPY, &c. 



Cuchineal for Staining No. 1 43 



44 

 52 

 52 

 55 

 59 

 59 

 62 

 65 

 71 

 72 



Prazmowski's Heliostat. (1 fig.) 



Laboratory for Microscopic Work 



A New Micrometer 



The Weber Slide. (I fig.) 



Orchella as a Staining Material 



Construction of Eye-pieces 



Iinpj'ovements in Micro-photography 



Measure for Covering-glass. (3 figs.) 



Method of representing an Object from Microscopic Sections 



Microscopy at the Paris Exhibition 



The Exact Orientation of the principal Section of Nicols in 



Polarizing Apparatus „ 74 



Improvements in Object-glasses. (1 fig.) „ 75 



Mr. Sorby's New Micro-spectroscope „ 81 



Dry Preparations of Diatoms, 4'c „ 83 



A New Method of Preparing a Dissected Model of an Insect's 



Brain from Microscopic Sections „ 84 



