72 SAN DIEGO SOCIETY OP NATURAL HISTORY 



RAYMOND (Percy E)— Continued 



genus the glabella does not reach to the front of the cephalon, nor does it expand to- 

 wards the front; it has also almost obsolete neck and dorsal furrows with a long and 

 narrow form. 



The author takes Isotelouirs If'liitfieldt for the tvpe. This species is the Asaphalus 

 canalis Whitfield, Bull. Am. Mus., vol. 1, p. 3 36, ;>1. 34, f. 1-8, not that of Conrad or 

 Hall. 



Hall credits the name to Conrad in MSS. and figures the livpostoma and doublure 

 from Chazy Village, New York. This is probably wliat is now known as Isotelus Harrisi 

 Raymond. 



On account of the facial suture termination at a point in tlie middle of the anterior 

 margin, the author classes as Isoteliform i.uture the genera Asapheilus, Asaphus and 

 Isotelus. 



In Niobe the suture cuts the anterior margin in front of the eyes, and follows around 

 the frontal margin, as in Nileus; classed as the Niobiform suture. 



The genera with forked hypostoma and with Isoteliform suture are arranged: 



Asaphidae — Asaphus, Onchometopus Ptych^tpyge, Isoteloides and Isotelus. Basilicus 

 is the only member with Niobiform suture. This form is common with the undivided 

 hypostoma as in Ogygia, Ptychocheilus, Asaphelina, Niobe, Symphysurus, lUaenurus, 

 Nileus Barrande, Homalopteon and Platypeltis. 



A few genera with undivided hypostoma have Isoteliform suture, namely: Megal- 

 aspis, Megalaspides and Asapheilus. 



The author ilescribes Asapheilus gyraccuitlius n. sp. (Asaphus canalis Cleland), A. 

 monticola. Subgenus to Niobe, Hemig\raspis n. gen. This genus is proposed with 

 Asaphus afflnis McCoy as a type. H. coU'ieana n. sp. 



The author includes Ogygia desiderata Barr. Niohe menapie?tsis Hicks, and A'. 

 sohiensis Hicks. Asapheilus planus Matt, in the genus. 



Megalaspis and Megalaspides. 



Sub-family Asaphidae: 



Asaphidae, hypostoma forked. 



Section 1 : Asaphidae with atiterior limli of facia! suture marginal Basilicus. 



Section 2: Asaphidae with anterior limb <if suture intra-marginal, P\ thopyge, 

 Pseudasaphus, Asaphus, Onchometopus, Isotelus, Isoteloides. 



The author describes and figures Asaphus marginalis Hall, under the genus Basi- 

 licus, including as the young of this species Asaphus alpha and A. gamma Raymond. 



The author remarks that the species is closely allied to Basilicus tyninnus Murch. 



The pygidium figured shows two lobes somewhat similar to that of Dicellocephalina 

 dicraeura Ang., as illustrated by Moberg, pp. 1-5, f. 14, Kongl. Fysiogr SoUsk. Handl., 

 Ang., Bd. 17, No. 7, 1906. 



Onchometopus ohtusus Hall. Isotelus harrisi Raym., /. platymargiriatus n. sp., /. 

 beta Raym. Isoteloides angusticaudus Raym. Xileus perkinsi n. sp. 



Subgenus Vogdesia. 



The thorax is similar to that of Nileus, as is the pygidium. The cephalon, which is 

 short and broad, is also similar to that of Nileus, but differs from it in having smaller 

 and much more elevated eyes, and deeper dorsal furrows. 



The author refers Nileus vigilans (M. & W.) as figured by Clarke, Palaeont. Min- 

 nesota, vol. 3, p. 713, and Isotelus hearsi Raym. to this genus. Thaleops arctura Hall, 

 refers Illaenus ovatus Raym. to this species. Bumastus glohosus Billings, B. erastusi 

 Raym., B. limhatus n. sp. A mphilichas minganensis Billings. Ceratophala narrozvayi n. 

 sp. Glaphurus pustulatus Wale, Cybele prima Raym. 



The author figures Pliomera fischcri Eicli. Pliomerops canadensis Bill., P. pseudora- 

 ticulatus Portk., P. barrandei Bill.. P. senilis Barr. Tlie new genus Pliomerops, with 



