BEITISH ASSOCIATION. 279 



light; preferring moderately humid, warm situations; one of the com- 

 monest of our species. It buries itself to a considerable depth in clay. 

 Locality : Ireland — Dublin ; everywhere. England — Kent, Chis- 

 selhurst, very common. (Three specimens (unnamed) in British Museum 

 Collection, from neighbourhood of London, belong, I believe, to this 

 species. They are stuck on cards, rendering examination impossible.) 

 Now first added to British lists. 



6. — P. armadilloides (Lereboullet), 



Synonyms : 0. convexus (Degeer), 0. saxatilis (Hartmann). 



Body elongated, elliptical ; segments very convex, smooth. Lateral 

 lobes minute, truncated in front. Median lobe very short, angular, 

 acute. Last ring of abdomen acute, plane, or slightly convex above. 



Colour : iron-gray, with clear borders to segments ; a band of white 

 blotches along either side of the median line. iNe^er having seen it 

 alive, cannot speak of its habits. Rolls itself into a perfect ball. 



Added to British lists on authority of six specimens in British Mu- 

 seum Collection (unnamed), which A. White, Esq., informs me were 

 captured near London (Highgate) (?) by Mr. Walker. 



7. — P. cingendus [n. s.) (mihi). Plate XIX., Fig. 1. 



Body elongate, ovate, smooth, or slightly scabrous. Lateral lobes 

 minute, rounded, directed downwards. Median lobe nearly obsolete, 

 arcuate. Terminal ring broadly triangular ; apex acute, plane above ; 

 a raised continuous line along upper margin of each ring. Whole ani- 

 mal shining, smooth, or covered with minute shining granulations only. 

 Closely allied to P. pruinosus, from which it differs chiefly in the 

 smooth, shining body, and the coxae of cephalo-thoracic rings having 

 their posterior angles rounded off. 



Colour : bright red and yellow blotches on a dark steel-gray ground. 



Habits : runs with extreme rapidity ; inhabits dry stations exclu- 

 sively, as under leaves ; never rolls itself into a ball. 



Localities : Dublin, very rare. 



The characters given above are constant, easily distinguishing it 

 from P. pruinosus, which, when young, resemble the parents. I can find 

 no description in authors approaching this species, and am, therefore, 

 compelled to give it a name. I find it both in company with P. prui- 

 nosus, and also alone. 



Family.— LIGID^E. 



Genus. — Ligia. 



1. — Ligia oceanica {Lin. sp.) 



Synonyms : Oniscus oceanieus (Linn.), P. aquaticus (Baxter), Cymo- 

 thoa oceanica (Fabric), Ligia oceanica (ib.). 



Body flattened, oval. Head transverse, covered with smooth gra- 

 nulations. External antennae shorter than body. Tige multi- articulate, 



