CHAPTER II 



THE BRANCHIOPODA 



SUB-CLASS BRANCHIOPODA, Latreille (1817). 



Order 1. Anostraca. 

 2. Notostraca. 

 3. Conchostraca. 

 ,, 4. Cladocera. 

 Sub-Order 1. Calyptomera. 

 Tribe 1. Ctenopoda. 



2. Anomopoda. 

 Sub-Order 2. Gymnomera. 



Tribe 1. Onychopoda. 

 2. Haplopoda. 



Definition. Crustacea in which the carapace may form a dorsal 

 shield or a bivalve shell or may be entirely absent ; the number of 

 trunk-somites varies greatly ; the posterior part of the trunk is 

 without limbs and usually ends in a caudal f urea ; the antennules 

 are generally reduced and unsegmented ; the mandibles have 

 no palp or only a vestige of one ; the maxillae are reduced or 

 absent ; the trunk-limbs, which vary greatly in number, are 

 generally of uniform structure, rarely pediform, generally foliaceous 

 and lobed ; the position of the genital apertures varies greatly ; 

 the paired eyes are rarely absent ; development usually with 

 metamorphosis ; young hatched in nauplius or metanauplius stage. 



Historical. The earliest mention of any of the Branchiopoda is 

 found in the works of Swammerdam, who, in 1669, described a 

 species of Daphnia as " Pulex aquaticus arborescens," and the name 

 of " water-fleas " has since been commonly applied to the group of 

 Cladocera. Apus and Branchipus were described early in the 

 eighteenth century, and, together with Daphnia, formed the sub- 

 jects of a series of remarkable memoirs (1752-1756) by J. C. 

 Schiiffer. The classical work of O. F. Miiller, Entomostraca .v // 

 Insecta testacea (1785), described a large number of new types and 



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