xxii LIST OF ILLUSTRATIONS 



FIG. PAGE 



87. Crayfish, gills -356 



88. Crayfish, diagram of circulation of blood 340 



89. Crayfish, early development 344 



90. Crayfish, early embryo in nauplius stage 345 



91. Crayfish, later embryo 346 



92. Mussel, side view, and shell 351 



93. Mussel, diagrammatic sections 353 



94. Mussel, dissection 356 



95. Mussel, structure of gill 358 



96. Mussel, circulatory system . 361 



9^. Mussel, advanced embryo and free larva 364 



98. Dogfish, side view 367 



99. Dogfish, diagrammatic sections 370 



100. Dogfish, skull 373 



101. Dogfish, vertebrae 376 



102. Dogfish, pectoral arch 378 



103. Dogfish, dissection 380 



104. Dogfish, vascular system 385 



iO4a. Dogfish, diagram of circulation 389 



105. Dogfish, brain ...... 392 



106. Dogfish, early embryo 398 



107. Dogfish, advanced embryo 399 



108. Mosses, various genera, anatomy and histology 402 



109. Funaria, reproduction and development 406 



1 10. Pteris and Aspidium, anatomy and histology 414 



111. Ferns, various genera, reproduction and development . . . 424 



112. Equisetum^ aerial shoot and spores 435 



113. Equisetum, reproduction and development . 437 



114. Sa/vmia, part of plant 439 



115. Salvinia, reproduction and development ........ 441 



116. Selaginella., part of plant and sporangia 443 



117. Selaginella, reproduction and development 445 



118. Pinus, sections of stem 449 



119. Gymnosperms, reproduction and development 453 



1 20. Pinus, stamen 455 



