INDEX. 



Notk. — After the semicolon the Roman numeral indicates the plate on which 

 the species is figured, and the following Arabic numeral refers to the figure. 

 Specific names to which no plate-number is given are regarded in the Monograph 

 as synonyms. Casual references are in italics. 



Amphigraptus 



distans 



divevgens 



124 

 122: 



var. radiatus 

 123: 



... 121 

 XVIII, 3 

 XVIII, 1 



— radiatus 



Amplexograptus 



arctus 



Angle of divergence . 



Aperture 



Azygograptus 



coelebs 

 — Hicksii 



XVIII, 2 



... 123 

 221, 267, 293 

 221, 271 ; XXXI, 16 

 ccelatus 221, 270 ; XXXI, 17 

 confertus 221, 269 ; XXXI, 18 

 perexcavatus 



221, 267; XXXI, 15 



6 



6 



92 



...97; XIII, 4 

 ...94; XIII, 2 



Lapworthi 



suecicus 



...93; XIII, 1 

 ...95; XIII, 3 



Branching, lateral and dichotomous ... 70 



Bryograptus ... ... ... ... ... 87 



— Callavei 84 



- — divergens ... ... 90; XII, 2 



Kjerulfi 88; XII, 3 



— var. cumbrensis 89 ; XII, 4 



— ramosus ... ... ... 88, 89 



Cepbalograptus 222, 285, 294 



— acuminatus 222, 289 ; XXXII, 1 1 

 cometa 222, 285 ; XXXII, 10 



— folium 282 



Cepbalograptus ovato-elongatus 

 petalum 

 — tubulariforrais 



Cladograpsus capillaris 



— Forchanmieri ... 



— gracilis 



— linearis 

 Clatbrograptus 



— cuneiform is ... 

 Climacograptus 



— antennarius 



277 



222,287 

 287; XXXII, 9 

 112 

 150 

 127 

 119 

 315 

 316 

 164, 182 

 ... 300 

 XXVII, 4 



199 



antiquus 



— var. liueatus 



201 ; XXVII, 5 



— var. bursifer 



201 ; XXVII, 6 

 bicornis ... 193; XXVI, 8 



— var. lougispina ... 193 



— var. tridentatus 



195 ; XXVI, 9 

 ■ — var. peltifer 



196 ; XXVI, 10 

 brevis ... 192; XXVII, 2 



caudatus ... 202 ; XXVII, 7 

 ccelatus 199, 270; XXXI, 17 



confertus ... 269 



extremus ... 210; XXVII, 13 

 Hughesii ... 208; XX VII, 11 

 innotatus ... 212 ; XXVII, 10 

 internexus ... ... ... 208 



latus ... 204; XXVII, 3 



medius ... 189; XXVI, 4 



69 



