CRUSTACEA SYSTEMATIC REVIEW 



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gurus, Birgus (in holes in the ground). Hippidce, marine, live in mud ; posterior 

 body hard skinned, the half of it bent forwards. The Galatcidce (Galatea) approach 

 the Macrura, and the Porcellanidce (Porcellana) the Brachyura. 



FIG. 203. Astacus fluviatilis, from the ventral side. A, male ; B, female. In the male the 

 8th to 13th and 15th to 18th extremities of the left side of the body are removed ; in the female the 

 2d and 4th to 13th of the right side. 3-13, Extremities of the cephalo-thorax ;\a r a^ anterior and 

 posterior antennae ; gd, aperture of the antennal glands ; wo, female ; mo, male genital aperture ; 

 PrPe, pleopoda ; en, endopodite ; ex, exopodite of the last pair of pleopoda ; an, anus ; t, telson 

 (after Huxley). 



Sub-Order 3. Brachyura (Crabs). 



Body flattened. Posterior body without anal fin, reduced, bent round on the 

 ventral side of the cephalo-thorax. In the male only the two anterior pairs 

 of pleopoda are usually retained. Notopoda, in the sea : Dromia, Dorippe, Lithodes. 

 Oxystomata, round crabs : Calappa, Ilia, in the sea. Oxyrhyncha, triangular crabs : 

 Maja, Pisa, Stenorhynchus, Inachus, Lambrus, in the sea. Cydometopa : Telphusa 



