100 SPHiEROCOCCOIDEiE. v. 



platycarpum both positions of tetraspores occur. Indeed T am by no means con- 

 vinced that Kiitzing's Neuroglossum Binderianum is specifically distinct from B. 

 platycarpum.^ 



Kiitzing has, as I think unadvisedly, referred Jeannerettia lobata, Hook, and Harv. 

 (Ner. Austr. t. 4.) to this place, overlooking the nature of its stichidia, which, in 

 my opinion, clearly indicate an affinity with Rhodomelacece. However, as the con- 

 ceptacular fruit is as yet unknown, it may be premature to regard the question 

 decided. 



1. BoTRYOGLOSSUM joZa<?/mr^?/m, Kiitz. ; sori of tetraspores (generally) lodged in 

 small leafy processes, which either fringe the margin or are dispersed over the 

 surfoce. Kiitz. Sp. Alg. p. 881. J. Ag. Sp. Alg. 2, p. 676. Fucus platy carpus, 

 Turn. Hist. t. 144. Delesseria platy carpa, Ag. Syst. p. 252. (Tab. XXI. A.) 



Hab. ]\Ionterey, California, Mr. Douglas ! Dr. Coulter ! Dr. Sinclair ! Capt. 

 Wilkes ! (v. V.) 



Root a large conical disc, throwing out lateral branches. Fronds twelve inches 

 long or more, irregularly di-trichotomous or palmate-parted, divided nearly to the 

 base into numerous linear-cuneate lacinioe, which are either simple, or again simi- 

 larly divided. The lower part of the frond and of its divisions is furnished with a 

 very broad, flat midrib, which spreads over the greater part of the disc. This 

 midrib is cartilaginous and very thick below, but becomes thinner and less defined 

 above, and at length disappears in the upper and wider portions of the cuneate 

 lacini«. In young fronds the margins of the laciniaj are either deeply crenate or 

 obtusely pinnatifid, the lobes being sometimes deep, sometimes shallow, always 

 very obtuse with bluntish or rounded interspaces. In some specimens the lacinia 

 is merely repand. In old plants the margin is frequently worn away and much 

 jagged, the membrane being reduced to a narrow wing-like border to the broad 

 midrib. In fertile specimens the eroded margin produces a multitude of minute, 

 leaf-like, I'oundish or lobed processes half a line to a line in breadth, sometimes 

 scattered, but more frequently densely crowded and forming a thick fringe to the 

 segment. In these processes are sometimes found tetraspores immersed in thicken- 

 ed central discs ; and sometimes conceptacles. The tetrasporic fruit is most com- 

 mon. A thin slice of the frond shows several rows of muriform cells, of which the 

 central row is of larger size. The outer row alone contains coloured matter. 

 When the membrane is viewed vertically, the surface appears areolated with hexa- 

 gonal cells, among which may be traced faint indications of internal, branching 

 veins. Colour a dark purplish red, becoming browner in drying. Substance carti- 

 laginous and thick. It scarcely adheres to paper in drying. 



The tetraspores are by no means confined to the marginal leaflets. In some of 



* Siiice this was prepaied for the press, I observe that Professor J. Agardh unhesitatingly unites tliese plants. Sp. Alg. 

 2, p. 676. 



