68 



STUDIES IN GEOLOGY,, No. 3 



BiCOrinol* forms with Cquol yrdj ot>Ov* 

 poiTenor can no-, wlwrls appear banded 



INCA 



* * 



155 



X / Sli^Htltf bicori not* forms virH 2 promiont one* 



q^ $;{ ing subsidiary -threads above tfct posW.'cr tarina 



IKC A vor.TRlTA 



Forms v'rt> on- corino, tfcc band oDsol** in odwlt 

 \ Whorl*; manif fin* intr*tihal throd^, tht aoprocor, n I 



Sorfttrr cenyvx, ni'ln an angular ctravati'tn ^ fnc f>o4t.r, r 

 porl { rf,, rvhrl 





NELSON I 



forms fw.'th rhf cor i no ebeol1, ftc wharls 

 , ihc scoljc^ur* much a* in MEL3o 



WEL50NI rar. KOTUNDATA 



Smell (mi w'rt) *> nrtnic Yvherl* 

 fltt aflolt whorls roundd, 



PREWOKCIA r. JKCOK5PICUA 



(l?ro i''ns indicate rarielal 



praminrnT e*rina, rhe sculp fi'r 

 a fn NC1.SOHI (4 main Mprorari nal tt>r/< ' v 

 K I fh oueroeorinal svri'arr ?!'', end no indfnt. 

 ^ 1 tion 1 *> po-jlt-rior part f rfi* whr( 



k I TRULLT5SATIA 



5 nirf> eon. tan<Hi rvhorlj. with rht seolp- / Shape f wKerl as n yar. Tipji.i3STiA , btrt 



as in INFR^CKinrV/HTA ~/ nerrxalli, w.rt> 5promino7 *i;pra*r.'n*l H.rra, 



X . ~- - !.-- ' - - - 



INFRACARINftTA 



Torn* i.rt> meneean' 

 nnerls, ivitn rnt italffon at 



Styractrinal }<Jfftf'e flat 



PRENUr(CIA 



showing iiatcr/i&.l 

 relationships of frwy oP 

 Titm'je 77* ne2so n i 



