INDEX. 



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

 for the page numbers. 



ACANTHOCEPHALA, 51 



Acarida, 135 

 Acineta, 3 

 Acmaea, 98 

 Acrania, 174, 185 

 Acridium, 136, 164 

 Actiniaria, 23 

 Actinophrys, 1, 6 

 Actinosphaerium, 1, 6 

 Actinozoa, 23, 34 

 Adelochorda, 174 

 ^Eginopsis, 22 

 JEolis, 98 

 Agalena, 135 

 Alcyonacea, 23 

 Alcyonaria, 23, 36 

 Alcyonium, 23 

 Amarcecium, 174, 181 

 Amoeba, 1, 4 

 Amoebina, 1 

 Amphineura, 97, 115 

 Amphioxus, 174, 185 

 Amphitrite, 78, 91 

 Annelida, 78 

 Anosia, 136 

 Antedon, 61 

 Anthomedusae, 22 

 Antipatharia, 23 

 Aphis, 136 

 Apis, 137, 170 

 Aplacophora, 98 

 Aplysina, 17 



Apoda, 61 

 Appendicularia, 174 

 Appendix, 187 

 Arachnida, 134 

 Arachnoidea, 134, 158 

 Araneida, 135 

 Arbacia, 60 

 Arcella, 1, 5 

 Arcbi-annelida, 78 

 Archi-chaetopoda, 78 

 Arenicola, 78, 93 

 Argonauta, 99 

 Argulus, 133, 156 

 Armata, 78 

 Arthostraca, 134 

 Articulata, 56 

 Ascaris, 51 

 Ascidiacea, 174 

 Ascidian, 176 

 Aspidobranchia, 98 

 Asterias, 60, 61 

 Asteroidea, 60, 61 

 Astrangia, 23, 36 

 Astropecten, 60 

 Astrophyton, 60 

 Aurelia, 23, 32 

 Autolytus, 78, 88 



BALANOGLOSSUS, 174, 175 

 Balanus, 133 

 Barnacle, 156 

 Bdelloura, 39, 41 

 207 



