220 CERAMIACEiE. v. 



their insertion, to falcate, incurved, leaf-like ramuli, a line or two in length, pecti- 

 nate or deeply inciso-dentate along the outer edge. Similar distichous pinnte 

 border all the branches at distances of a line or two apart, alternating with each 

 other, but opposing minute, multifid ramuli of equal length or very much shorter. 

 These ramuli, carelessly examined, appear to be mere heads of densely crowded 

 divaricato-multifid ramelli ; but are really composed on the same pinnated type as 

 the rest of the frond, one pinnule being falcate and pectinate, the other pinnato- 

 multifid, or if fertile, altered into a glomerulus of tetraspores. Colour, a full red, 

 brownish when dry. Substance rigid, not adhering to paper. 



A very remarkable and distinct species. I have examined an authentic frag- 

 ment of Agardh's P. densa, preserved in Sir ^Ym. J. Hooker's Herbarium, and find 

 it to agree perfectly with my more recently named P. peetinaia. The latter name 

 is therefore suppressed. 



Plate XXXH. B. Fig. 1. Ptilota densa ; the natural size. Fig. 2, portion of a 

 branch, with pectinate pinnaj, and opposing multifid, fertile ramuli ; Jig. 3, a ra- 

 mulus, with clusters of tetraspores ; Jig. 4, tetraspores ; the latter figures more or 

 less magnijied. 



2. Ptilota hgp7ioides, Harv. ; frond piano-compressed, two-edged, decompound- 

 pinnate ; pinnae opposite, unlike ; one undivided, leaf-like, lanceolate or ovato- 

 lanceolate, acute, very entire ; the other elongated, pinnated with similar lanceolate 

 acute pinnae opposing ramuliform processes ; tetraspores aggregated in oblong 

 glomerules, alternating with the pinnules of the lesser branches. Harv. in Bot. 

 Beech, p. 164. /. Ag. Sp. Alg. 2, p. 97- Kutz. Sp. Alg. p. 670. (Tab. XXXH. 

 A.) 



Hab. California, Messrs. Lay anA Collie, (v. s. in Herb. T. C. D.) 



Fronds six to eight inches long, or probably much more, half a line in diameter 

 at the base, compressed, two-edged, decompound-pinnate ; the primary branches of 

 very unequal lengths, long and short intermixing together, closely pinnated 

 throughout at distances of a line or two. One of the pinnae is a simple, leaf-like, 

 lanceolate or ova to-lanceolate, acute ramulus, a line in length, never altering with 

 age ; the opposite pinna is a branchlet which is either abortive and rudimentaiy, or 

 lengthens out into a branch which is closely pinnated with lanceolate leaf-like pin- 

 nules (like those of the larger branches) opposed to minute, pinnulated branchlets 

 of their own length or shorter. These latter occasionally elongate, and are com- 

 pounded in a similar manner to the larger branches ; and thus the frond continues 

 to be developed. When fertile, however, they remain short, and consist then of 

 lanceolate pinnellse alternating with stalked, oblong clusters of tetraspores. Colour, 

 a rosy purple. Substance, cartilaginous and firm. In drying, it does not adhere to 

 paper. 



A beautiful species, and perhaps not rare ; but as yet very few specimens have 

 found their way to Europe. It was first found by liajnke, whose specimens were 



