A DISCUSSION ON BREATHING 141 
of the trunk and the epimera and by two ducts under the 
insertion of the pleon. In Hthusa the case is the same. 
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Fig. 11 —Ranina scabra (Fabricius), a male specimen, with separate figure of the pleon 
[de Haan]. 
In Calappa and Matuta the hinder ducts are not below but 
close to the pleon over the first joints of the fifth pair of 
