AUSTRALIAN HYDROMEDUS.E. 23 



IV. Sub-familia DICRANOGRAPTINJE. Von Lendenfeld. 

 DICRANOGRAPTID^E. Lapworth. 



Hydrosome consists of two originally dorsally united axes. Cells overlapping. 

 Exterior part indented. Broad end of the sicula on the proximal end of the 

 hydrosome. 



B. DIPRIONID.E. 



Cells in two rows ; axis central. 



V. Sub-familia DIPLOGRAPTINJE. Von Lendenfeld. 

 DIPLOGRAPTIDJE. Lapworth. 



Hydrosome consists of two branches dorsally joined. Sicula imbedded. The 

 broad part forming the proximal end of the hydrosome. 



16. Genus DIPLOGRAPSUS. McCoy. 



Stems simple, straight, with a slender central axis ; cells oblique in t\vo 

 vows, alternating often with two spines near the exterior opening. 



. r )5. Diplograptus mucronata. Hall. (94) 470, (104) 20. 

 Bulla, Victoria. 



50. Diplograptus pristis. Hisinger. (94) 470, (104) 11. 

 Victoria. 



57. Diplograptus rectangularis. McCoy. (94) 470, (104) 

 Bulla, Victoria. 



5S. Diplograptus palmeus. Barrande. (94) 471, (105) 32. 

 Bendigo, Victoria. 



17. Genus CLIMACOGRAPTUS. Hall. 



Cells vertical free, in section sub-oval, divided from each other by deep 

 cavities, without ornament or with a simple marginal spine ; hydrosome taper- 

 ing, in section circular, or divided into two naps ; axis prolonged beyond the 

 distal end. 



59. Climacograptus bicornis. Hall. (94) 471, (104) 12. 

 Victoria. 



VI. Sub-familia PHYLLOGRAPTINJE. Von Lendenfeld. 

 PHYLLOGRAPTIDJE. Lapworth. 



Hydrosome consists of four monoserial axes, which coalesce with their dorsal 

 sides. Sicula imbedded. The broader ends close to the proximal terminations 

 of the hydrosomes. 



18. Genus PHYLLOGRAPTUS. Hall. 



Leafshaped, cells rectangular, the lateral surfaces touching. Outer touching 

 with two protruding spines. 



59. Phyllograptus folium. Hisinger. (94) 471, (104) 7. 

 Victoria. 



