Ser. RuoDOSPERMEiE. Pam. Sph(Erococcoide(B. 



Plate CLXXIX. 



DELESSERIA FRONDOSA, iiooL/d. d Harv. 



Gen. Char. Frond leaf-like^ membranous, areolated, symmetrical, simple 

 or branclied, midribbed. Fructijication : 1, hemispherical concep- 

 tacles, sessile on the midrib or on a lateral nerve, containing a tuft of 

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

 in definite sori or spots, on the frond or on accessory leaflets, — 

 Delessema {Ag.), in honour of Baron Delessert, a distinguished 

 patron of botany. 



JFrons foliacea, memh'anacea, areolata, symmetrica, simplex v. ravwsa, costata. 

 Fruct.: 1, coccidia in casta venisque frondis sessilia, Jiemisphcei'ica, fila spori- 

 fera monilifoimia a placenta hasali emissa foventia ; 2, tetrasporce triangule 

 divisce, in soros definitos collectce. 



Delesseria frondosa ; frond subsessile, repeatedly pinnatifid (very vari- 

 able in breadth and outline), curled or plain, the marginal lobes 

 rounded or obtuse, serrulate ; midrib vanishing upwards, ribs of the 

 lacinise and their lobes obsolete at base and apex ; cystocarps solitary 

 on the midribs of the ultimate segments, apiculate ; sori in rows 

 along the margin of the smaller segments. 



D. frondosa ; fronde suhsessili decomposite piunatifida (polymorpha, angusta v. 

 latissima, ovata v. linear i-lanceolata, etc.) crispata v. planiuscula, lacinulis 

 apice rotiindatis margine serrulatis ; casta superne evanescente, castulis lacini- 

 arum et lacinidarum hasi et apice obsoletis ; cystacarpiis in costa lacinularum 

 solitariis sessilibus apicidatis ; soris secus marginem lacinularum seriatis, 



Delesseria frondosa, Hool-. fil. et Harv. Land. Jour. Bat. v. 6. p. 403. 

 /. Ag. Sp. Alg. v. 3. p. 689. Harv. in Hook. fit. Ft. Tasm. v. 2. p. 312 ; 

 Alg. Austr. Exsic. n. 284. 



Hemineura frondosa, Harv. Ner. Austr. p. 116. t. 45. 



Hypoglossum frondosum, Kutz. Sp. Alg. p. 876. 



Hab. In deep water. Very abundant on the coasts of Victoria and of 

 Tasmania ; rarer, and of small size in Western Australia. 



Geogr. Distr. Western and southern coasts of New Holland. Tasmania. 



Descr. Foot a small disc. Fronds tufted or solitary, 3-6-12-24 inches long, 

 and as much in breadth, sometimes nearly simple, sometimes excessively 

 compound, always on an alternately pinnatifid type. Stem scarcely any, ex- 

 cept iu very old and partly denuded fronds. Primary leaf varying from 

 ovate or oblong to lanceolate and narrow-linear, with an immersed, nearly 

 percurrent midrib, which is broad and strongly marked below, but becomes 

 narrower and fainter upwards, and almost or quite vanishes just below the 

 summit. The lateral lacinicB are short or long, and usually linear, but 



