(P SAN DIEGO SOCIETY OF 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, i 
The author takes Isoteloides Whitfeldi for the type. This species is the Asaphalus 
canalis Whitfield, Bull. Am. Mus., vol. 1, p. 336, pl. 34, f. 1-8, not that of Conrad or 
Hall. 
Hall credits the name to Conrad in MSS. and figures the hypostoma and doublure 
from Chazy Village, New York. This is probably what is now known as Isotelus Harrisi 
Raymond. 
On account of the facial suture termination at a point in the middle of the anterior 
margin, the author classes as Isoteliform suture the genera Asaphellus, Asaphus and 
Tsotelus. 
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 Ptychopyge, 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, Illaenurus, 
Nileus Barrande, Homalopteon and Platypeltis. 
A few genera with undivided hypostoma have Isoteliform suture, namely: Megal- 
aspis, Megalaspides and Asaphellus. 
The author describes dsaphellus gyracanthus n. sp. (Asaphus canalis Cleland), ,A. 
monticola. Subgenus to Niobe, Hemigyraspis n. gen. This genus is proposed with 
Asaphus affinis McCoy as a type. H. collieana n. sp. 
The author includes Ogygia desiderata Barr. Niobe menapiensis' Hicks, and N. 
solvensis Hicks. Asaphellus planus Matt. in the genus. 
Megalaspis and Megalaspides. 
Sub-family Asaphidae: 
Asaphidae, hypostoma forked. 
Section 1:  Asaphidae with anterior limb of facial suture marginal Basilicus. 
Section 2: Asaphidae with anterior limb of suture intra-marginal, Pythopyge, 
Pseudasaphus, Asaphus, Onchometopus, Isotelus, Isoteloides. 
The author describes and figures dsaphus marginalis Hall, under the genus Basi- 
licus, including as the young of this species dsaphus alpha and A. gamma Raymond. 
The author remarks that the species is closely allied to Basilicus tyrannus 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 Séllsk. Handl., 
Ang., Bd. 17, No. 7, 1906. 
Onchometopus obtusus Hall. Isotelus harrisi Raym., I. platymarginatus n. sp. 1. 
beta Raym.  Isoteloides angusticaudus Raym. Nileus 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 Jsotelus bearsi Raym. to this genus. Thaleops arctura Hall, 
refers I/laenus ovatus Raym. to this species. Bumastus globosus Billings, B. erastusi 
Raym., B. limbatus n. sp. Amphilichas minganensis Billings. Ceratophala narrowayi n. 
sp. Glaphurus pustulatus Wale., Cybele prima Raym. 
The author figures Pliomera, fischeri Eich. Pliomerops canadensis Bill., P. pseudora- 
ticulatus Portk., P. barrandei Bill., P. senilis Barr. The new genus Pliomerops, with 
