degrees of actual relationship between the different forms, so far as this relationship can be discovered. In the next chapter a brief sketch of the chief subdivisions of the Crustacea is given, with such details as to the characteristics of each as are necessary to render intelligible the succeeding chapters on their habits and modes of life. CHAPTER III THE CLASSIFICATION OF CRUSTACEA _Table of Classification of Crustacea_ CLASS CRUSTACEA. Subclass BRANCHIOPODA - {Order Anostraca. { " Notostraca. { " Conchostraca. { " Cladocera. " OSTRACODA - { " Myodocopa. { " Podocopa. " COPEPODA - { " Eucopepoda. { " Branchiura. " CIRRIPEDIA - { " Thoracica. { " Rhizocephala. " MALACOSTRACA. Series _LEPTOSTRACA_ - " Nebaliacea. " _EUMALACOSTRACA._ Division _Syncarida_ - " Anaspidacea. " _Peracarida_ - { " Mysidacea. { " Cumacea. { " Tanaidacea. { " Isopoda. { " Amphipoda. " _Eucarida_ - { " Euphausiacea. { " Decapoda. " _Hoplocarida_ - " Stomatopoda. [Illustration: FIG. 10--THE "FAIRY SHRIMP" (_Chirocephalus diaphanus_), MALE. × 2. (After Baird.)]