23. 



L. 



24. 



L.? 



25. 



L.? 



26. 



L.? 



27. 



L. 



28. 



L. 



29. 



L. 



30. 



L. 



No. 5] REVISED SYSTEM. SURVEY OF THE MELOBESIEAE. 19 



L. expansum f. exigua Fosl. 



(f. involvens Vin.) 

 22. L. incrustans Phil. 1 ) (incl. L. ponderosum Fosl?) 



f. depressa CCrn ) Fosl. (incl. f. flabellata Heydr.) 



f. Harveyi Fosl. (incl. f. labyrinthica Heydr. saltem ex parte). 



f. angulata Fosl. (incl. f. subdichotoma Heydr.) 



f. lobata Fosl. 



orbiculatum Fosl. (L. incrustans f.?) 



asperulum (Giimb.) Fosl. 



Goldfussi Giimb. 



Kotsclwanum Unger. 



grumosum Fosl. 



onkodes Heydr. (excl. specim. cum „concept. cystoc") 



Crouani Fosl. 



amplexifrons (Harv.) Rosan. 



Subgen. II. Carpolithoil Fosl. 



Conceptacles of sporangia scarcely raised above the surface 

 of the frond, the whole roof at length decorticated ; the disc less 

 •overarched. 



31. L. decipiens Fosl. 



32. L. discoideum Fosl. 



Subgen. III. Lepidomorphum Fosl. 



Conceptacles of sporangia immersed or subprominent, forming 

 convex prominences on the surface of the frond frequently equi- 

 valent only to a part of the roof, at length partly decorticated ; 

 the disc more or less overarched, connected vvith the roof by a 

 central, attenuating plug and delicate filaments. 2 ) 



v ) Cfr. Lithothamnion polymorphum Vin. 



f. incrustans. 



f. confluens. 



f. crustacea. 



•f. stalactitica. • 



f. tuberculata. 



f. lata. 

 - 2 ) The bipores quoted L c. especially in this subgenus formerly referred to 

 Goniolithon are not to be considered as such and do not run through 

 the roof. 



