CKUSTACEA. 649 



Sp. Scrolls Fabricii LEACH, Cymothoa paradoxa FABR., BUCKLAND M ineral. 

 and Geology, London, 1836. PI. 45, figs. 6, 7 (after a drawing by CURTIS), 

 Cuv. R. Ani. ed. ill., Crust. PI. 64, fig. 3, &c. This genus in the two 

 longitudinal furrows on the back of the trunk bears a strong resemblance 

 to the fossil Trilobites, but there is no proper affinity on this account. 



Family XVI. SpJiceromida. Body broad, oval, frequently con- 

 tractile into a ball. Head large, broad. Feet not fixing themselves 

 by hooks. Tail small, mostly composed of only two segments, the 

 first five having coalesced to form one. The last pair of caudal 

 feet with only a single moveable lamella extended near the outer 

 side of pygidium. Foot-jaws resembling palps. 



Ancinus EDW. First and second pairs of feet terminated by a 

 large moveable hook, subcheliform ; remaining feet gressorial, 

 slender, terminated by a straight claw. Body depressed, plane. 

 Antennas long, setaceous. 



Sp. Ancinus depressus MILNE EDWARDS, Hist. not. des Crust. PI. 32, fig. 17. 



Sphceroma LATE. Feet of trunk all gressorial, slender, termi- 

 nated by a short claw, often bifid. Body gibbous above, contrac- 

 tile into a ball (Onisci globatores). 



Sp. Sphceroma serratum LEACH, Oniscus globator PALLAS, Spicil. Zool. ix. 

 Tab. 4, fig. 18, DESMAR., Crust. PI. 47, fig. i ; from 2'" to more than 5'" 

 long, in the Atlantic ocean, the Mediterranean and the Black Sea. 



Note. Genus Zuzara LEACH is scarcely distinct. 



Add sub-genera : Cymodocea LEACH, Ncesea LEACH (and CUic&a 

 ejusd.), Campecopea LEACH, Cerceis EDW., Ampkoro'idea EDW., Cassi- 

 dina EDW. 



Family XVII. Pranizidea. First two segments of trunk in- 

 distinct or joined with the head, destitute of feet. Five pairs of 

 feet of trunk. Antenna four, setaceous, unequal. Posterior part 

 of abdomen or tail with six segments, supplied with foliaceous 

 appendages at the apex. 



Anceus Risso, Gnathia LEACH. Head large, almost square, 

 armed anteriorly with two horns porrect, falcate (mandibles?). 



Sp. Anceus forficularius Risso, DESMAR., Crust. PI. 46, fig. 7 (not fig. 6), 

 GUERIN Iconogr., Crust. PI. 27, fig. 7; Anceus maxillaris LAM., Cancer 

 maxillaris MONTAGU, Linn. Trans, vn. 1804, Tab. vi. fig. 2, DESMAR. 

 Crust. PI. 46, fig. 6. 



