130 



CRUSTACEA PERACARTDA 



male, aii.cl upon which the female organisation is imposed as the 

 parasitic habit is assumed. 



The following is a list of the Epicarida with the Crustacea 

 which serve as their hosts l : 



Cryptoniscina< 



Microniscidae on 



Cryptoniscidae on 



Liriopsidae on 



Hemioniscidae on 



Cabiropsidae on 



Podasconidae on 



Asconiscidae on 



Copepoda. 



Ostracoda. 



Rhizocephala. 



Cirripedia. 



Isopoda. 



Amphipoda. 



Schizopoda. 



fDajidae } 



I Phryxidae 

 Bopyrina 



j Bopyndae j 



\ Entoniscidae J 



on Decapoda. 



In 



all cases the first larval form which hatches out from the 



maternal brood-pouch is called the 

 Epicaridiaii larva (Fig. 85). 



This little larva has two pairs 

 of antennae, a pair of curious frontal 

 processes, and a pair of mandibles. 

 The other mouth-parts are missing ; 

 there are only six thoracic limbs, 

 but the full complement of six 

 biramous pleopods are present, and 

 at the end of the body there may 

 be a long tube of unknown function. 

 As a type of the Cryptoniscina 

 we may take the Liriopsidae," 

 parasitic on the Rhizocephala, 

 which are, of course, themselves 

 parasitic on the Decapoda, the whole 

 association forming a very remarkable study in Carcinology. 



Almost every species of the Rhizocephala is subject to the 

 attacks of Liriopsids, the latter fixing either on the Rhizocephala 

 themselves, or else on the Decapod host at a point near the 

 fixation of the Rhizocephalous parasite. An exceedingly com- 

 mon Liriopsid is Dancdia curvata, parasitic on Sacculina neglecta, 



1 Bonnier, Trans. List. Zool. Lille, viii., 1900. 



2 G. Smith, Fauna and Flora Ncapcl, Monograph 29, chap. vi. ; M. Caullery, 

 Mitth. Zool. Stat. Neapel, xviii., 1908, p. 583. 



FIG. 85. Epicaridian larva, probably 

 belonging to one of the Crypto- 

 niscina. A, 2nd antenna; Ab, 

 abdominal appendages ; T, thor- 

 acic appendages. (From Bonnier, 

 after Hansen.) 



