IV. =CYCADOXYLEAE= 185–190 =Cycadoxylon= 185–187 =Ptychoxylon= 187–190 V. =CALAMOPITYEAE= 190–200 =Calamopitys= 190–196 _Kalymma_ 194–196 =Eristophyton= 197–200 VI. =CLADOXYLEAE= 200–210 =Cladoxylon= 201–207 =Völkelia= 208–210 VII. =PROTOPITYEAE= 210–213 =Protopitys= 210–213 CHAPTER XXXIII CORDAITALES. Pp. 214–299. A. =POROXYLEAE= 214–219 =Poroxylon= 214–219 B. =CORDAITEAE= 219–284 =Cordaites= 219–265 _Noeggerathiopsis_ 238–243; _Rhiptozamites_ 244, 245; _Phylladoderma_ 244; _Euryphyllum_ 245; _Artisia_ 246–248; _Dadoxylon_ 248–260; _Metacordaites_ 260, 261; _Cordaianthus_ 264–270; =Mesoxylon= 270–275; =Pelourdea= 277–281; =Niponophyllum= 282, 283; =Titanophyllum= 283, 284. CHAPTER XXXIV C. =PITYEAE= 285–299 =Pitys= 285–289 =Archaeopitys= 290 =Callixylon= 291–293 =Coenoxylon= 293, 294 =Parapitys= 294, 295 =Mesopitys= 295, 296 =Antarcticoxylon= 296–299 CHAPTER XXXV PALAEOZOIC GYMNOSPERMOUS SEEDS. Pp. 300–365. I. +Lagenostomales+ 308–318 =Physostoma= 309–312; =Conostoma= 313–316; =Sphaerostoma= 316; =Lagenostoma= 316; =Gnetopsis= 317, 318. II. +Trigonocarpales+ 318–332 =Trigonocarpus= 319–321; =Tripterospermum= 321; =Ptychotesta= 321; =Hexapterospermum= 321–323; =Polypterospermum= 323; =Pachytesta= 323–326; =Stephanospermum= 326–329; =Polylophospermum= 329, 330; =Codonospermum= 330, 331; =Aetheotesta= 331, 332; =Eriotesta= 332; =Gaudrya= 332.