78 Annals of the Carnegie Museum. 



impressed as in this species. In this last character and the presence of a 

 median depression on the frontal lobe it resembles Pliomera. It was for 

 trilobites of this type of glabellar structure that the name Ileliomera was 

 proposed, with Cheirunis sol Billings as the type. 



Locality. — Upper part of the lower Chazy at Chazy, New York. The 

 plesiotype is in the Museum of Yale University. The original specimens 

 described by Billings were from Table Head and near Portland Creek, 

 Newfoundland. 



Genus Sph^rocoryphe Angelin. 



Sphaerocoryphe goodnovi Raymond. 

 Plate XIX, figures 16-18. 

 Since this species was published more material has been obtained, 

 which makes it possible to give somewhat better figures. The genal 

 angles are found to bear long, round, slightly curved spines. 



Explanation of Plates. 



Unless otherwise indicated, figures are natural size, and the specimens are in 

 the Carnegie Museum. 



Plate XVII. 



1. Isolelns karyisi Raymond. A cranidium from Isle La Motte, now in the 

 Vermont State Museum. 



2. Isotelus plalymarginatus Raymond. A cast taken from the natural mould 

 shown in figure 3. 



3. The same species. A natural mould from Isle La Motte, Vermont. Ver- 

 mont State Museum. 



4. The same species. A large pygidium from Acidaspis Point, Valcour Island, 

 New York. 



5. The same species. A free cheek from the lower part of the Chazy at the 

 southern end of Valcour Island. About three times natural size. 



6. Basilicus marginalis (Hall). A large pygidium showing the peculiar notch 

 in the posterior margin. Sloop Bay, Valcour Island, New York. Yale University 

 Museum. 



7. Isoleloides angusticaudiis Raymond. A cephalon from Isle La Motte, 

 Vermont. Vermont State Museum. 



Plate XVIII. 



1. Isoleloides angusticaudus Raymond. An entire, but imperfect specimen from 

 Isle La Motte. Slightly larger than natural size. Vermont State Museum. 



2. Onchometopus obtusus (Hall). Cephalon and thorax of an enrolled indi- 

 vidual in the Vermont State Museum. From Isle La Motte, Vermont. 



3. The same specimen. Thorax and pygidium. 



4. The same species. A pygidium from Valcour Island showing the large 

 punctae of the shell. 



