INDEX. 



References to directions for the study of forms are indicated by the use of boldface 

 type for the page numbers. 



ACANTHOCEPHALA, 46 



Acarida, 126 

 Acineta, 3 

 Acmoea, 90 

 Acrania, 164, 173 

 Acridium, 127, 154 

 Actiniaria, 19 

 Actinophrys, 1, 4 

 Actinosphserium, 1, 5 

 Actinozoa, 19, 30 

 Adelochorda, 164 

 iEginopsis, 18 

 iEolis, 90 

 Agalena, 126 

 Alcyonacea, 19 

 Alcyonaria, 19, 32 

 Alcyonium, 19 

 Amaroecium, 164, 170 

 Amoeba, 1, 3 

 Amoebida, 1 

 Amphineura, 89, 106 

 Amphioxus, 164, 173 

 Amphitrite, 70, 83 

 Annelida, 70 

 Anosia, 127 

 Antedon, 55 

 Anthomedusffi, 18 

 Antipatharia, 19 

 Aphis, 127 

 Apis, 128, 159 

 Aplacophora, 90 

 Aplysina, 14 



Apoda, 55 

 Appendicularia, 164 

 Appendix, 175 

 Arachnida, 125 

 Arachnoidea, 125, 147 

 Araneida, 126 

 Arbacia, 54, 61 

 Arcella, 1, 4 

 Archi-annelida, 70 

 Archi-chaetopoda, 70 

 Arenicola, 70, 85 

 Argonaut a, 91 

 Argulus, 124, 146 

 Armata, 70 

 Arthostraca, 125 

 Articulata, 50 

 Ascaris, 46 

 Ascidiacea, 164 

 Ascidian, 165 

 Aspidobranchia, 90 

 Asterias, 54, 55 

 Asteroidea, 54, 55 

 Astrangia, 19, 31 

 Astropecten, 54 

 Astrophyton, 54 

 Aurelia, 19, 27 

 Autolytus, 70, 80 



Balanoglossus, 164 

 Balaniis, 124 

 Barnacle, 146 

 Bdelloura, 35, 37 



195 



