PLATE 3. 



62. Phryganea (larva). 



63. Dytiscus (head of larva). 



64. (larva). 



65. Colymbetes fuscus. 



66. Ilybius ater (hairs on anterior tarsi). 



67. (labn.m). 



68. ,, ,, (mandible). 



69. (first maxilla). 



70. ,, ,, (labium, or second maxillae). 



71. Elaphrus uliginosus. 



72. Culex (larva). 



73. (pupa). 



74. (imago). 



75. Limnochares holosericeus. 



76. Arrenurus globator. 



77. Rana temporaria (pigment cells from skin). 



78. Molge (larva). 



79. Nostoc. 



80. Tolypothrix. 



81. Oscillaria. 



82. Closterium moniliferum. 



83. ,, ,, (vacuole). 



84. Closterium acerosum. 



85. Cosmarium tetraophthalmum. 



86. Mougeotia. 



87. Spirogyra. 



88. (conjugating filaments). 



89. Zygnema. 



90. Pinnularia oblonga. 



91. Pandorina. 



92. Volvox globator. 



93. ,, ,, (portion more highly magnified). 



94. Pediastrum. 



95. Oedogonium. 



96. Coleochaete. 



97. ,, (portion more highly magnified). 



98. Vaucheria. 



99. Hydrocotyle vulgaris (transverse section of petiole, portion of). 



100. Juncus (transverse section of stem, portion of). 



(N.B. During the process of reproduction the figures have been 

 reduced by l-20th.) 



