118 DICTYOTACE^.— AsPEROcoccus. iv. 



Hab. Rocks, &c. between tide-marks. Annual. Boston Bay, G. B. Emerson 

 (fide Prof. J. W. Bailey.) (v. v.) 



Very variable in size. Fronds from a few inches to two feet in length, and from 

 the thickness of hog's-bristle to half an inch in diameter, linear-club-shaped, taper- 

 ing to the base. The apex is either obtuse, or somewhat attenuated. The dots of 

 fructification are crowded, and often entirely cover the surface. 



I have not seen American specimens, but give this species on the authority of my 

 friend Prof. Bailey, merely remarking that Chorda lommtaria is often mistaken for it^ 

 and has been sent to me from America for the Asperococcus. The true A. ecliinatus is 

 however so common in the Northern Atlantic, that it is most probably to be found 

 on many parts of the American coast. It may be known from Ch. lomeniaria by 

 being never constricted into joints. 



2. Asperococcus sinuosus^ Bory ; fronds globose, or irregular, heaped together, 

 sessile, inflated, at length irregularly distorted and torn. J. Ag. SjJ. Alg. vol. 1. 

 j9. 75. Encoelium sinuosum, Ag. — Kiitz. Sj). Alg. p. 552. (Tab. IX. C.) 



Hab. On rocks, corals and Alg£e between tide-mai^ks. On the Florida Keys. 

 Yery abundant at Sand Key, and washed ashore at Key West, W. H. H. (v. v.) 



Fronds growing in dense clusters which cover spaces of many inches or some 

 feet square. Each individual frond is globose, one or two inches in diameter, or 

 larger, becoming much inflated and irregular in outline as it advances in age, and 

 is then often ruptured, and pierced here and there with holes of irregular shape 

 and size. The frond is membranous, thin, soft, but not very tender, having a 

 reticulated appearance, from the large interior cells composing the inner lining of 

 the membrane ; and with a smooth uniform surface, from the minute cells which 

 compose the superficial coating : it thus follows that with lenses of difierent powers 

 the frond appears either areolated or of densely cellular structure. Such fructifi- 

 cation (?) as I have seen consists in minute sori., dotting over the surface, and 

 composed of linear, moniliform paranemata^ formed at first under the membranous 

 coating of the frond, and bursting through it : — but I have not detected any 

 spores. Colour a brownish olive. 



In habit this plant strongly resembles Leathesia tuberiformis (common on the 

 shores of the Northern States) but is of a totally different structure, and can only 

 be confounded with that plant through carelessness or inattention 



Plate IX. C. Fig. 1. Cluster of Asperococcus sinuosus ; the natural size ; 

 fig. 2, a minute portion of the surface ; fig. 3, vertical section of a sorus ; fig. 4, 

 p)aranemata from the same ; the latter figures highly magnified. 



