66 CARBONIFEROUS AMMONOIDS OF AMERICA. 



Septa consisting of a broad, obtusely rounded ventral lobe, with a 

 very small siphonal indentation; lateral lobe shallow, acute, funnel-shaped; 

 ventral and lateral saddles broad, shallow, with circular ends. 



Winchell compares this species with GhjpMoceras striolatum Phillips, 

 from Avhich it differs in the smaller umbilicus, larger ventral lobe, and 

 ventral saddles. The description, however, would make it appear that this 

 species in nearer to Glyphioceras mutabile Phillips. 



Occurrence. — Supposed to have come from the Lower Carbonifei-ous (?), 

 Kinderhook stage, Marshall group. Battle Creek (?), ]\[ich. 



Genus GoNiATiTES de Haan. 



When Hyatt undertook a revision of the goniatites in his Genera of 

 Fossil Cephalopods he did not include Goniatites itself in his list, but 

 included the type of all this stock in his new genus Glyphioceras. Many 

 years before this de Haan " had described and figured the genus Goniatites, 

 using G. spl}(Prkus Martin as the type; in so doing, he complied with all 

 the laws of nomenclature, and no genus stands on a firmer basis than this. 

 Therefore when it has been found that de Haan included under this name 

 many species of diverse orgin, it is quite proper to give separate generic 

 titles to these; but the type of the original genus can not receive any new 

 name, and must always stand for the original species and all like it. 



Hyatt'' first mentions Goniatites splicericus under the description Glyphi- 

 oceras, and therefore this species is to be regarded as the type of the genus, 

 rather than G. crenistria, which authors usually cite as the type. Hyatt 

 divides the genus Glyphioceras into two sections: 



I. Involute globose shells, including such forms as Goniatites sphccricus 

 Martin, G. crenistria Phillips, and G. striatus Sowerby. 



II. Forms with compressed whorls, and open umbilici, including Gonia- 

 tites ohtusus Phillips as type of the section, G. diadema Goldfuss, G. platylohus 

 Phillips, G. harhotanus M. V. K., and others. Of this second section,- G. 

 diadema can not be included in the same genus with G. sphcBriciis, and either 

 a new name will have to be given it or else Hyatt's name will have to be 

 restricted to this section. E. Plaug ' proposes to restrict the name Goniatites 



"Mon. Amnion. etGon., 1825, p. 159. 



Troc. Boston Soc. Nat. HiBt, Vol. XXII, p. ,S2«. 



<' Etudes sur les Goniatites, p. 26. 



