714 SCHUCHERT AND TWENHOFEL ORDOVICIC-SILURIC SECTION 



Feet 



graptus clintonensis (common), Mesograptus, Bilohites Mlohus, 

 Brachyprion leda, ScUucliertella snliplana, Triplecia ortoni 

 (rare), Clorinda n. sp., Zygospira cf. modesta, Atrypa reticu- 

 laris, Anoplotheca hemispJierica, Spirifer radiatus meta, Nncleo- 

 spira 11. sp., Clionychia nitida (common), Oncoccras futile, 

 Platyceras cf. niagarense (small), Calymene vogdesi (3 inches 

 long, same in Clinton of Ohio and New York), Illwnus (large 

 new species), Acaste orestes, Encrintirus punctatus ?. Lichas cf. 

 'boltoni 80 



Oncoceras futile heds. 



E4. Same limestones as E3, but gradually passing into purer limestone. 



Fossils the same as in E3, but without the graptolites 22 



Eg. Ash gray, hard, conchoidally fracturing, thin-bedded limestones 

 abounding in Oncoceras futile. Other fossils are Favosites goth- 

 landicus, Atrypa reticularis, Anoplotheca hemispheric a (large 

 and lamellose here), Stricklandinia lens, Clionychia nitida, 

 Calymene cf . vogdesi, and Acaste orestes 43 



Stricklandinia lens Veds. 



Eg and E7. Same petrographic character as below. Stricklandinia lens 



in profusion. Otherwise the fauna is that of below 13 



Es and Eg. Same petrographic character as below. The common 

 species here are Favosites gothlandicus, Monograptus clintonen- 

 sis, many bryozoa, Dalmanella elegantula, Orthis fladelUtes, 

 Brachyprion leda, Clorinda 11. sp. (same in Dg), Stricklandinia 

 lens (rare here), Pentamerus oMongus (rare), Atrypa reticu- 

 laris, Anoplotheca heniispherica, and Acaste orestes 138 



E,o. Measures largely concealed. 



At the Jumpers, 2 to 3 miles east of Southwest light-house, 

 the terminal 20 feet of this zone may be seen abounding in 

 fossils — one of the richest localities on the island — but the 

 variety is not so large. Some of the fossils are Favosites goth- 

 landicus, F. venustus, Flectamhonitcs truKSvcrsalis, Lcptwna 

 Julia, Brachyprion leda, Strophonella genicuhtta Shaler (not 

 Hall), Stricklandinia Virata, S. hrcvis, Pentamerus ohloiigus. 

 Anoplotheca hentispherica, Spirifer radiatus meta, Leperditia 

 (very large), Acaste orestes, Calymene vogdesi 158 



Correlation. — The Jupiter Eiver faunas are clearly of Clinton aspect, 

 retaining at the base the Ohio or older phase derived from the preceding 

 Gun Eiver formation, while the higher strata, with their abundance of 

 Pentamerus ohJongtis, are clearly related to the New York Clinton. This 

 correlation is further strengthened by the fact that the life of the follow- 

 ing Chicotte formation is in harmony with the northern N'iagaran faunas 

 of the upper Mississippi Valley. 



