CE USTAOEA—SYSTEMA TIC RE VIE JV 



299 



gurus, Birgus (in holes in the ground). Hq)picla:, marine, live in mud ; posterior 

 body hard skinned, the half of it bent forwards. The Galateidcc {Galatea) approach 

 the Maa-ura, and the Porcellanicloi {Porcellana) the Bmchyura. 



Fro. 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 ; ai-a^, anterior and 

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

 Vi^Qf 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 iin, 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. 

 Oxystamata, round crabs : Calappa, Ilia, in the sea. Oxyrliyncha, triangular crabs : 

 Maja, Pisa, StenorhyncAus, Inachus, Lamirus, in the sea. Cydmietopa : Telphusa 



