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 common Liriopsid is _Danalia curvata_, parasitic on _Sacculina neglecta_, which is itself parasitic on the spider-crab, _Inachus mauritanicus_, at Naples. The adult _Danalia_ is a mere curved bag full of eggs or developing embryos, and without any other recognisable organs except two pairs of spermathecae upon the ventral surface where the spermatozoa derived from the larval males are stored. [Illustration: FIG. 86.—_Inachus mauritanicus_, ♀, × 1, carrying two _Sacculina neglecta_ (_a_, _b_), and a _Danalia curvata_ (_c_), the latter bearing two dwarf males. ] In Fig. 86 is represented a female of _Inachus mauritanicus_ which carried upon it two Sacculinae and a _Danalia curvata_, and upon the latter are seen two minute larval males in the act of fertilising the adult _Danalia_. The eggs develop into the Epicaridian stage, after which the larva passes into the Cryptoniscus stage (Fig. 87). In this larval form the segments are clearly delimited; the only mouth-parts present are the mandibles, but there are seven pairs of thoracic limbs and the full number of pleopods. This Cryptoniscus stage is found in all the Epicarida, and only differs in detail in the various families. [Illustration: FIG. 87.—Ventral view of Cryptoniscus larva of _Danalia curvata_, ♂, × 25. ]