276 Scientific Intelligence. 
the strata; and leaving out a few forms which gradually disappear in 
the western extension of the formation, the paleozoic evidence might’be 
regarded as decidedly favoring this view. The distinction, however, be- 
tween Devonian an arboniferous faunas is based as often upon geo- 
graphical as chronological relations. 
The species of Spirifera in the Upper Helderberg group are, S. duo- 
denaria, macra, raricosta and Griert, occurring both in the Schoharie 
grit and in the limestone above; which latter likewise contains the fol- 
only in the limestones of this age in Ohio and adjacent States of Indiana 
and Kentucky. 
e mete 
form ; in the Chemung, S. taiabeanice mesastrialis, disjuncta, with o 
numerous synonyms and the species represented in a great variety 
aspects, alia (n.s.), prematura (n. s.). 
The chapter on Spirifera is concluded with some remarks upon the ge0- 
logical and geographical distribution of the species of Spirifers, the hinge 
Structure, etc., which have already been published.* oa 
_ the name Amboccelia is continued, being regarded as presenting sul 
cient distinction from Spirifera; and in the Hamilton group are . 
ized, Ambocelia wmbonata, .A. preumbona, in the Chemung group; A. 
gregaria, : 
On page 263 of the volume are some observations on the genus ger 
of Dalman, and Cyrtina of Davidson. So long since as in 1858, ¥f 
some doubts as to the value of the genus Cyrtia of Dalman; and 
later investigation had shown that the typical species of that genus does 
iri ime, some forms usually referred 
* Ks . 
ee nse *pecles are described in the present volume from the — 
= ork, viz: Oyrtina biplicata, from the Schoharie grit; crassa (0 ‘ 
Professor Hall alluded to on page 408 of vol. xliii of this Jou 
Y Written article as might be iehecret from the note, but as Be 
pages of his volume rv. 
