EFICARIDA LIFE-HISTORY OF BOPYKUS 



133 



caridian and Cryptoniscns stages, a further larval state is assumed, 

 called the Bopyrus, which is the functional male, and, after per- 

 forming this function, passes on to the adult female condition. 



The family Bopyridae is parasitic in the branchial chamber 

 of Decapoda, especially Macrura and Anonmra. When one of 

 these Decapods is infested with an adult Bopyrid the gill-chamber 

 in which it is situated is greatly swollen, as shown in Fig. 90. 

 A very common Bopyrid is Bopyrus fougerouxi, parasitic in the 

 gill - chambers of Palaemon serratvs. The Bopyrus larva or 



FIG. 90. Galathea intermedia, with 

 a 1'leurocrypta microbranchiata, 

 under its left branchiostegite 

 (), x 1. (Alter Sars.) 



FlG. 91. Ventral view of male 

 Bopyrus fongerouxi, x 30. 

 A, 1st and 2nd antennae ; 

 T, 8th (last) thoracic ap- 

 pendage. (After Bonnier.) 



functional male has the appearance shown in Fig. 91. It 

 differs from the Cryptoniscus stage in possessing a rudimentary 

 pair of anterior thoracic limbs and seven pairs normally 

 developed, while the abdominal limbs are plate - like and 

 branchial in function. The male can often be found attached 

 to the female beneath the last pair of incubatory lamellae. 



The adult female condition, which is assumed after the 

 Bopyrid stage is passed through, is illustrated in Fig. 92. 

 The body acquires a remarkable asymmetry, due to the unequal 

 pressure exerted by the walls of the gill - chamber. The 

 antennae and mandibles (Fig. 92, B) are entirely covered up by 

 the largely expanded maxillipedes ; maxillae are, as usual, entirely 



