FREDEHICELLIDiE. 



PLUMATELLIDiE. 



I CRI8TATELLID.T 



Id^^""'"'""''' 



udti'orcnt,'''' """^ ' 



zZ. 





horlzontnl. 



1 ll 



rrrascs! 



^ffrS3£ 



wholly lost c 



rrogulnrly divided by 



eiaan, iSepreiBi-l, 

 ccUs ofthe Bccondlaycr 



fuUy dovPloped, 

 ad itiKl 4th favors nd- 



throughout , 



ullydevfli.|iKd. 



waUs entire orpartiaUy 



ponnancntlv divided 



l^^moncSiB or gola- 

 ccIIb orthe Bccond Wcr 



;Vr'.7ighror sljghtly bent 

 ut iLu undo, 



^Mply^^olonlSir 



permanent during the 



ceUaorthc second layer 

 mily de^v^lo^od,^^ ^^ 



^he?e to thBY"mcm- 

 branc throughout, 



riinj-'Sovei'opcd, 

 eUiptlcSl, ''°' 



decidedly bent nt the 

 polntudat theendB, ' 



lIply'^oloXT 



found only on tLo uii- 

 largo an& promlocat, 



calla of the Bocond layer 

 ftiUy developed, 



3d and 4th layora ad- 

 here to the k mom- 

 hrnoe thronghout, 



mily developed, 



dcpreaaod oruloDgnted 



loo^-SBOmmWl'. 

 bent at the ends. 



HpVccloS'e 



larj^^a^d mo 



ftilly dovolo 



ftilly"dovck.p 

 elllpUcal. 

















arise from si. 







cndocydt, ] iiiembruDos fully de- 



















fUlly developed, 

 mgUuM^pBratcdbyn 



