SUBCLASS I 



TEILOBITA 



721 



Family 15. Proetidae Corda. 



Small Opistho'paria ivith cephalon and pygidium nearly equal, free cheeks large, eyes 

 long, and close to the glabella. Thorax with eight to ten segments. Ordovician to 

 Permian. 



Proetus Steininger (Figs. 1351, 1364, G ; 1389) 

 furrows. Pygidium smaller than cephalon. 

 Ordovician to Carboniferous ; Europe, 

 Asia and America. 



Gyphaspis Burmeister. Similar to 

 Proetus, but with a strongly elevated 

 ridge which surrounds the glabella out- 

 side the dorsal furrows. Glabella with 

 prominent basal lobes. Ordovician to 

 Devonian ; Europe and America. 



Haploconus Eaymond. Similar to 

 Gijphaspis, but without the basal lobes on 

 the glabella. Type, Bathyurus smithi 

 Billings. Ordovician ; North America. 



Phillipsia Portlock (Fig. 1390). 

 Similar to Proetus, but with large pygi- 

 dium, and basal lobes on glabella 



Glabella witliout deep lateral 



Fk;. 1390. 



Fig. 1389. 



rroetus , bohemims Corila. 

 This Silurian (Et. E) ; Konieprus, 

 . -1 1 • Bohemia (after Barrande). 



genus survived all other trilobites, but 



became extinct with the close of the Permian. Carboniferous and Permian ; 



Europe and America. 



PhiUipsin gernmulifera 

 Phill. Lower Carboni- 

 ferous ; Kildare, Ire- 

 land. 



Aeglina Barrande (Fig. 1391). 



A l: ( • 



Family 16. Aeglinidae Pictet. 



Opisthoparia with large glabella and. eyes which occupy nearly the whole area of the 

 free cheeks. 



This genus has the glabella strongly convex, 

 prominent, smooth ; fixed cheeks suppressed ; 

 eyes very large ; thoracic segments five or six ; 

 pleura grooved ; pygidium large, with short axis. 

 Ordovician ; Europe. 



Family 17. Lichadidae Corda. 



Opisthoparia with large cephalon and pygi- 

 dium, the glabella greatly modified by the peculiar 

 development of the lateral furrows. Thorax with 

 nine or ten segments. Pygidium with short 

 axial lobe, and the pleural lobes modified in 

 various ivays. Ordovician to Devonian. 



Fig. 1301. 



Aeglina iiHaca Barr. Ordovician (Etage D) ; 

 Vosek, Bohemia. A, Nat. size. B, C, enlarged 

 (after Barrande). 



Lichas Dalman (Figs. 1364, /; 1392). 

 The glabella is broad, with axial furrows which 

 do not reach the neck furrow. Occipital lobes are present. Pygidium flat, with 

 the pleural lobes divided by furrows into two pairs of lobes with short free ends, and 

 a median flattened lobe. Ordovician and Silurian ; Europe and America. 



Amphilichas Raymond {Platymetopus Schmidt). Glabella large, divided longi- 

 tudinally into three lobes by a pair of axial furrows which join the neck ring. 

 Ordovician ; Europe and America. 



Gonjdocephalus Corda (Figs. 1338, A; 1393). Glabella with three pairs of side lobes, 

 VOL. I 3 A 



