V. LAURENCIACE^. 73 



termediate in character between L. ohtusa and the Australian L. Forsteri, Grev. 

 (Turn. Hist, t.n.) 



Plate XVIII. D. Fij. 1. hxuRE'SCiA im^jlicata ; a branch, the natural size. Fig. 2, 

 a portion, somewhat rnagnljied. 



5. Laurencia cervicornis ; frond terete, robust, irregularly branched, subdicho- 

 tomous ; the secondary branches curved upwards, spreading to all sides, having a 

 few secund, cylindrical, obtuse rainali ; axils rounded ; conceptacles broadly ovate 

 with a projecting orifice, sessile near the tips of the ramuli. (Tab. XVIII. C.) 



Hab. Key West, W. H.H. (31), Dr. Blodgetl. 



Tufts globose, somewhat fastigiate. Fronds as thick as crow's quill, 4-5 inches 

 long, much branched from the base, bushy, very irregular in ramification, the 

 branches spreading widely and directed to eveiy side, curved upwards, of some- 

 what equal height, making a loosely corymbose head, naked, or having along their 

 upper side, at distances of a quarter to half an inch, several cylindrical, secund 

 ramuli. Rarmdi erecto-patent, obtuse, quite simi)le or ramulose at the tip, from a 

 quarter to half an inch long or more. Conceptacles at or near the ends of the 

 branches, partly imbedded, very broad in proportion to their length, with a project- 

 ing, acute orifice. Colour a dark brownish red. Substance rigid, scarcely adhering 

 to paper. 



Seemingly allied to L. Forsteri, but more robust than the strongest grown speci- 

 mens of that species, and less dichotomous. 



Plate XVIII. C. Fig. 1 , a branch of Laurencia cervicornis, the natural size. 

 Fig. 2, apex of branch, with conceptacle ; fig. 3, spore ; both magnified. 



6. Laurencia gemmifera ; fronds robust, cartilaginous, fragile, terete, flexuous, 

 irregularly much branched ; branches patent, alternate, unequal, irregularly pinnate 

 or bipinnate, set throughout with minute, bud-like, horizontal, scattered, spi- 

 rally disposed, truncate ranmli. (Tab. XVIII. B.) ^. decompound-pinnate, the 

 pinna3 tolerably regular and very patent. 



Hab. Florida Keys. Key West, W. H. H. (34), Dr. Blodgdt (36) var. ^. Key 

 West, W. H. H. (30), Frqf. Tuomey (30, 38, 53), Dr. Blodgett (49). (v. v.) 



Fronds growing in large, loose bundles, G — 8 inches long, as thick as crow- 

 quill, shrinking in drying, much and very irregularly branched, the branches spread- 

 ing toward every side, and subspirally inserted, alternately or irregularly scattered, 

 very flexuous, having secondary branches at distances of a quarter to half an inch. 

 These branches are of very unequal length, long and short intermixed, and are 

 patent, with rounded angles, and much curved or arched, and sprinkled throughout 

 with exceedingly minute, bud-like ramuli. Famuli spirally disposed round the 



VOL. IV. ART. 5. L 



