SPECIES OF PIS1DIUM. 47 



(PI. XIX, f. 15 a) and from Bohemia (PI. XIX. f. 12 a). Both 

 the lust two instances occur in association with an oval form 

 (PI. XIX, f. 156 & 12 b) that outwardly resembles P. pusillum ; 

 as also do examples from Church Close, Mortehoe, Devon (PI. XIX, 

 f. 10). 



An approach to P . yersvnatum is seen in some specimens like those 

 from Gt. Gaddesden, Herts (PI. XIX, f. 14 & 37 a, 6). Trigonal 

 forms recalling P. casertanum in miniature are those from Louth, 

 Lincolnshire (PJ. XIX, f. 25), Button Coldtield, Warwickshire 

 (PI. XIX, f. 29 a, 6), and the fossil example from the Holocene 

 of Newbury (PI. XIX, f. 27). 



The amount of inflation varies from the normal as represented 

 in the Lough Pern specimens (PL XIX, f. 5) to the more tumid 

 forms from Tenhy (PI. XIX, f. 4) or in the direction of compression 

 to that from the Lea Valley (PI. XIX, f. 7). 



DISTRIBUTION. 



81 

 01 



NS CA 

 HB SS 



RW RE EL BF AN 

 8 Wl El PN AS 

 AM PM FF XI 

 M DN 86 PC KF 



1 CT RF LL ED HO 



AY LA PE BW NN 



WD ED LD AN WT KB u F SK RX 8N 



F TY AR OJ| CU WL NY DM 



WM SL LE MO ML MY EY 



EM RO CV LH SL WY 8Y LH 



we NG LF WH ME CK DB FT CH DY NM L8 



SB KG D DU MN MG SP ST LR B WN EJj 



CL NT QC CW Wl CD RA HF WO WW NO HII JB 



NK U 8T KK WX PB CM BR GE X X BD (jj NE 



SK MC EC WA GM MM GW NW BJJ MX SE 



WC NS W NH S_R-J.K EK 



ND SS DT SH WX EX 

 E C SO I W 



sc wc 



Cl 



Pisidiuw nitidum. 



(Recent occiurences are showu in red: fossil occurrences Ly a Hue 

 below the symbols. For the explanation of the symbols see p. 20.) 



