Ser. RHODOSPERMEiE. Fam. Sphcerococcoidece. 



Plate LIX. 



DELESSERIA SERRULATA, Haw. 



Gen. Char. Frond leaf-like, membranaceous, areolated, symmetrical, sim- 

 ple or branched, midribbed. Fructification: 1, hemispherical con- 

 ceptacles, sessile on the midrib, or on a lateral nerve, containing a 

 tuft of moniliform spore-threads on a basal placenta ; 2, tripartite 

 tetraspores, in definite sori or spots, on the frond, or on accessory 

 leaflets. — Delesseria {Ag.) } in honour of Baron Delessert, a distin- 

 guished patron of botany. 



Frons foliacea, membranacea, areolata, symmetrica, simplex v. ramosa, costata. 

 Fr. : 1, coccidia in costa venisque frondis sessilia, hemispherica, fila sporifera 

 monil if ormia a placenta basali emissa foveutia ; 2, tetraspora triangule divisa, 

 in soros definitos collects. 



Delesseria serrulata ; frond linear-lanceolate, repeatedly proliferous from 

 the thick midrib with leaflets of a similar form ; leaflets sharply ser- 

 rulate ; conceptacles on the midrib of the younger leaflets, near the 

 apex ; sori on each side of the midrib. 



D. serrulata ; fronde lineari-lanceolata repetite prolifera ; foliolis a costa crassis- 

 sima vage prorumpentibus argute serratis ; coccidiis in costa foliolorum sub 

 apice sessilibus, sorisque elongatis idroque latere costce subsmgulis. 



Delesseria serrulata, Harv. Alg. Austr. Fxsic. n. 277. Harv. in Ferry's 

 Exp. to Japan, Bot. Appendix, p. 331. 



Hab. Dredged in Port Jackson, New South "Wales, Charles Moore, Esq. 



Geogr. Distr. East coast of Australia. Japan, Br. Morrow. 



Descr. Root a conical disc. Frond 6-12 inches long (or more), linear-lanceo- 

 late, undivided, from £— \ inch in breadth, tapering to each end, and tra- 

 versed by a broad, incrassated midrib, which is sometimes one-third the 

 breadth of the frond, sometimes narrower. This primary frond emits irre- 

 gularly from its midrib numerous secondary fronds of similar shape, but 

 smaller ; and these, in like manner, emit a third and fourth series of leaf- 

 lets, until the general frond becomes much branched and bushy. In very 

 old specimens the main frond is gradually denuded of membrane and changed 

 into a stem. All the leaflets are linear-lanceolate, but they vary in degree 

 of attenuation, and in the acute or obtuse apex. The margin is invariably 

 sharply serrulate, a character only visible under the microscope. Coccidia 

 hemispherical, near the apices of the youngest leaflets. Sori not yet found 

 on Australian specimens. The colour is a blight rosy-red. The substance 



