122 GELIDIACE^. 



V. 



are six or eight inches long, undivided, but furnished with copious lateral second- 

 ary branches, which are either similarly decompound once or twice or are furnished 

 with a few scattered, short, erect or spreading ramuli. Sometimes the division is 

 carried on to many sets of alternate branches and ramuli, and then the fronds are 

 exceedingly bushy ; sometimes the frond divides near the base into many virgate 

 branches having a second series of naked secondaries, two to four inches long. All 

 the lesser branches and ramuli are linear-fusiform, tapering to a much contracted 

 base and attenuate to a fine point. Conceptacles obtusely conical, half sunk in the 

 branches and ramuli, through which, in fertile specimens, they are plentifully scat- 

 tered. Tetraspores dispersed. Colour a dark red, becoming blood red on exposure. 

 Substance somewhat cartilaginous, but tender, decomposing in fresh water. In dry- 

 ing, it shrinks much and closely adheres to paper. 



I have many varieties of this sportive plant from the American shores. At Fort 

 Hamilton, New York, Mr. Hooper pointed out to me a squarrose form of a very 

 dark colour, more slender than usual, the branches distorted and very irregular and 

 the ramuli either patent or recurved : and Capt. Pike and Mr. Calverley have since 

 communicated many similar specimens from Red Hook. At first sight this form 

 looks very distinct from the deep-water varieties, but the microscopic structure is 

 the same, and I hesitate to separate it specifically. The Apalachicola specimens also 

 have a slightly different aspect from the common form. 



Before I had seen the fructification of this species I believed it to be a Bhahdonia 

 and had distributed it among my friends as R. Bai/eyi, named in compliment to 

 Prof Bailey, from whom I received the earliest specimens. It so perfectly resem- 

 bles in ramification the West Indian R. tenera, J. Ag. that except by the structure of 

 the sporiferous nucleus, which Prof Agardh has examined in the latter, I do not see 

 how they are to be distinguished. 



Plate XXIII. A. Fig. 1. Solieria chordaUs, the natural size. Fig. 2, longitudi- 

 nal section of a branch, with tetraspores in situ ; /?</. 3, tetraspores ; Jig. 4, trans- 

 verse section through a branch and conceptacle ; Jig. 5, small portion of the same, 

 to show structure more plainly -jjig. 6, spores ; the latter figures more or less highly 

 magnijied. 



IV. HYPNEA. La?nour. 



Frond cylindrical, cartilaginous, irregularly mucli branched and set with awl-shaped 

 ramuli. Axis consisting of a few slender, longitudinal filaments or filiform cellules, 

 (sometimes wanting) ; intermediate stratum of several rows of oblong, polygonal 

 cells, void of endochrome ; periphery of one or two rows of minute, coloured cel- 

 lules. Conceptacles hemispherical, without orifice, formed on the ramuli, and con- 

 taining numerous roundish clusters of pedicellate spores attached to slender, par- 

 tially anastomosing filaments which traverse the cavity. Tetraspores transversely 

 parted {zoned), clustered together in swollen ramuli. 



