10 SAN DIEGO SOCIETY OF NATURAL HISTORY 
BEECHER (Charles E,)—Continued 
Compound paired eyes absent; simple eyes may occur on each fixed cheek singly 
or in pairs. 
Including the families Agnostidae Dalman, Fam. 2, Harpeididae Barrande, Fam. 3, 
Trinucleidae Barrande. 
The first family includes the genera Agnostus Brongniart and Microdiscus (Em- 
mons) Salter. 
The second family, the genera Harpes, Goldfuss, Harpina Novak and Harpides 
Beyrich, 
The third family, Trinucleus Lhwyd, Ampyx Dalman, Dionide Barrande, Endy- 
mionia Billings, Lonchodomas Angelin, Raphiophorus Angelin and Salteria W. 
‘Thompson. 
Order B Opisthoparia. 
Free cheeks generally separate, always bearing the genal angles. 
Facial sutures extending forwards from the posterior part of the cephalon within 
the genal angles, and cutting the anterior margin separately, or rarely uniting in front 
of the glabella. 
Compound paired holochroal eyes on free cheeks, and well developed in all but the 
most primitive families. 
Fam. 4, Conocoryphidae Angelin, including the genera and subgenera. 
Conocoryphe Corda Aneucanthus Ang. Atops Emmons, Avalonia Walcott, Bailiella 
Matthew, Bathynotus Hall, Carausia Hicks, Carmon Bar. 
Ctenocephalus Corda, Dictyocephalites Bergeron, Eryx Ang., Harttia Wale. and 
Toxotis Wallerius. 
Family 5, Olenidae Salter, including the genera. 
Olenus Dalm. and the following genera and subgenera, which should fall into 
several sub-family or even family groups. 
Acerocare Ang., Acrocephalites Wallerius, Agraulus Corda, Angelina Salter. 
Anomocare Ang., Anopolenus Salter, Asaphelina Bergeron, Bavarilla Barr. 
Bergeronia Matthew, Boeckia Brégger, Ceratopyge Corda, Chariocephalus Hall. 
Corynexochus Ang., Crepicephalus Owen, Ctenopyge Linnarsson, Cyclognathus Linrs, 
Dikelocephalus Owen (Centropleura Ang.), Dorypyge Dames. 
Ellipsocephalus Zenker, Elliptocephala Emmons, Euloma Ang., Eurycare Ang., 
Holmia Matthew, Hydrocephalus Barr. (young Paradoxides), Leptoplastus Ang., 
Liostracus Ang., Loganella Devine, Menocephalus Owen, Mesonacis Walc., Micmacca 
Matthew, Neseuretus Hicks, Olenelloides Peach, Olenellus Hall, Olenoides Meek, 
Oryctocephalus Wale., Paloeopyge Salter, Parabolina Salter, Parabolinella Brégger, 
Paradoxides Brong., Peltura Ang., Plutonides Hicks, Proceratopge Wallerius, Prota- 
graulos Matthew, Protolenus Matthew, Protopeltura Brogger, Protypus Walc., 
Pterocephalia Roemer, Ptychaspis Hall, Ptychoparia Corda, Remopleurides Portlock, 
Sao Barr., Schmiditia Marcou, Solenopleura Ang., Sphaerothalmus Ang., Telepus Barr., 
Triarthrella Hall, Triarthrus Green, and Zacanthoides Walc. 
A number of genera have been made the types of family divisions, as Paradoxides, 
Olenellus, Remopleurides, Ellipsocephalus, Ptychoparia, etc. 
Family 6, Asaphidae Emmrich, including the genera and subgenera. 
Asaphus Brong., Asaphellus Callaway, Asaphiscus Meek, Barrandia McCoy, Ba- 
silicus Slater, Bathyurellus Billings, Barthyuriscus Meek, Bathyurus Bill, Bolbocephalus 
Whitfield, Brachyaspis Salter, Bronteopsis W. Thompson, Dolichometopus Ang., 
Gerasaphes Clarke, Holasaphus Matthew, Homalalopecten Salter, Isotelus Dekay, 
Megalaspides Brégger, Megalaspis Ang. Niobe Ang., Ogygia Brong., Ogygiopsis 
Walc., Phillipsinella Novak, Platypeltis Callaway, Ptychopyge Ang. and Stygina. 
glina Barr., 
The author includes under Illaenidae the genera Illaenus Dalm., A 
