BHITISH ASSOCIATION. 277 



Colour : general ground light-gray or bluish, ' with blotches and 

 patches of yellow, generally lineally arranged; a salmon-coloured variety 

 with dark patches occasionally met near sea. 



Habits : semi-rolls, and feigns death. 



Habitat : under decayed vegetable and animal matter, as well in 

 the dryest as wettest localities. Common near sea. 



Localities : Ireland — east coast generally. England — Kent, London, 

 &c. Appears to be common everywhere, but the species have not been 

 distinguished. 



2. — Oniscus fossor (H. Scliceffer, D. Crus., Cah. 22, n. 22). 



Synonyms : Oniscus muscorum (Lereboullet, p. 29). I cannot speak 

 of the other synonyms given by the author, as he has confounded it with 

 Philoscia muscorum. P. tceniola (Koch), given by him as a synonym, 

 is figured as a true Porcellio by Schseffer. The figure of 0. fossor is very 

 characteristic. 



Body oval, covered with numerous rough granulations, which give 

 it a powdered appearance; head convex; lateral lobes moderate, rounded; 

 frontal line produced into a triangular lobe which belongs to head, not 

 to antennal ring ; terminal ring and other characters as 0. murarius, 

 than which the whole animal is much smaller. 



Colour similar to 0. murarius, but paler. 



Habits : semi-rolls, and feigns death; much more active than 0. mu- 

 rarius. 



Habitat : dryish places, as under stones, dry leaves. 



Localities : Ireland — Dublin (Wexford, E. Percival Wright, Esq.). 

 England — Epping Eorest, Kent. Very common among the chalk-pits 

 at Chisselhurst ; now first recorded as British. (Three specimens in 

 British Museum Collection undistinguished from 0. murarius.) 



Genus. — Poecellio (Lat 

 1. — P. scaler (Latreille). 



Synonyms: Oniscus asellus (Linn), 0. granulatus (Lam.). Por- 

 cellio dubius, affinis et mult. al. (H. Schceff.), P. Brandtii (M.-Edwards). 



Body elongate, oval, rugous. Lateral processes very salient ; ex- 

 ternal angle rounded; median process triangular ; terminal ring ending 

 in a triangular point, acuminate, deeply sulcate in the median line. 



Colour : uniform grayish-black, yellow blotches on dark ground ; a 

 nearly uniform salmon-coloured variety also met with; there may be 

 two species confounded. 



Habit: runs with agility; semi-rolls itself; attacks living caterpillars. 



Habitat : moist places, everywhere there is decaying matter ; among 

 sea-weed on sea- shore along with Ligia, &c. The paler varieties are 

 found in the dryer localities. 



Distribution : apparently everywhere, and very common ; carries the 

 young all through the summer. 



vol. iv. 2 o 



