36 
PALEONTOLOGY OF NEW YORK. 
S. raricostus, Conrad, 
(?) 8. Knappianus, Nettelroth, 
(?) S. disparilis, Hall, 
S. zic-zac. Hall = S. consobrinus, 
D’Orbigny, 
S. mesacostalis. Hall, 
2. Aseptati; 
a. Mucronatus-type: 
S. segmentus. Hall, 
S. arctisegmentus. Hall, 
S. mucronatus, Conrad, 
8. bidorsalis, Winchell, 
S. sculptilis. Hall, 
8. Hobbsi, Nettelroth, 
8. Byrnesi, Nettelroth, 
S. varicosus. Hall, 
S. subattenuatus. Hall, 
S. bimesialis. Hall, 
8. desideratus, Walcott, 
Upper Helderberg group. 
Upper Helderberg group. 
Upper Helderberg group. 
Hamilton group. 
Chemung group. 
Upper Helderberg group. 
Upper Helderberg group. 
Hamilton group. 
Hamilton group. 
Hamilton group. 
Hamilton group. 
Hamilton group. 
Hamilton group. 
Hamilton and Chemung groups 
Hamilton and Chemung groups 
Lower Carboniferous. 
b. Submucronatus-type: 
(S. Engelmami, Meek and Worthen= 
8. Worthenanus, Schuchert, 
S. submucronatus. Hall, 
S. Cumberlandise, Hall, 
S. rnacrus. Hall, 
8. Davisi, Nettelroth, 
(?) S. gregarius, Clapp, 
Oriskany sandstone. 
Oriskany sandstone. 
Oriskany sandstone. 
Corniferous limestone. 
Corniferous limestone. 
Corniferous limestone. 
III. Fimbriati; 
1. Unicispinei =Delthyris, Dalman, 1828; 
a. Crispus-type; 
S. crispus, Hisinger, Niagara group. 
S. crispus, var. simplex. Hall, Niagara group. 
S. Vanuxemi, Hall, Lower Helderberg group. 
S. Saffordi, Hall, Lower Helderberg group. 
S. cyclopterus. Hall, Lower Helderberg group. 
