408 ALG^E DIATOMACEiE. [Licmophora. 



Ag. Conspect. Crit. Diat. p. 44. Berk. Brit. Alg. p. 14. t. 4.f. 2. 

 — Echinella obtusa, Lyngb. Hydroph. Dan. t. 69. 



Rivulets (Ag.). On wet rabbit-dung, Rev. M. J. Berkeley. — Form- 

 ing a thin stratum. Frustula hyaline, with two yellowish bands. Mr. 

 Berkeley observed some of the frustula to be of an elliptical form, with 

 rather obtuse apices. 



Tribe XXIV. Styi»larie,e. 



Frustula plane, wedge-shaped. 



104. Styllaria. Ag. Styllaria. 



Frustula wedge-shaped, separate, stemless, not united into 

 plane lamina?. — Name; probably from <frv7.og, or stylus, a column, 

 pillar or support ; since, according" to Bory, who invented the 

 name, the species which he considered to belong to it, are "stipi- 

 tated Echinellce" If so, the word should be Stylaria. (Hook.) 



1. S. cuneata, Ag. (wedge-shaped Styllaria); frustula with a 

 transverse band of yellow granules, the extremity erenato- 

 dentate. Ag. Conspect. Crit. Diat. p. 38. — Echinella cuneata, 

 Lyngb. Hydroph. Dan. p. 211. t. 70. 



Parasitic on the filiform marine Algce. Appin, Captain Carmichael. — 

 The specimens, communicated by this gentleman, are extremely minute, 

 and may possibly prove to be distinct. Two other species are described 

 by Agardh, one of which is found in fresh-water. 



105. Licmophora, Ag. Licmophora. 



Frustida wedge-shaped, flabelliform, stipitate. — Name; 

 Atx/jtiOtpogo;, fan-bearer ; highly expressive of the form of these 

 minute but beautiful objects. 



1. L. Jurgensii, Ag. (Jurgens Licmophora); stipes very short, 

 frustula subternate bipartite. — Ag. Conspect. Crit. Diat. p. 42. 

 — Echinella cuneata, Jurg. Decad. 19. 



Parasitic on the smaller marine Algce. Appin, Captain Carmichael. — 

 A very indifferent specimen is before me ; but it agrees tolerably well 

 with the plant to which I have referred it. 



2. L. splendida, Grev. (shining Licmophora); tufted, when 

 dry green and glistening, stipes elongated much branched, the 

 branches alternate, frustula wedge-shaped, both the lateral and 

 terminal ones flabelliform. 



Parasitic on marine Algce and Zoslera marina; Appin, Capt. Carmichael. 

 — A very fine species ; nearly allied to the following one, but smaller, 

 less divided, and the frustula more broadly wedge-shaped. The tufts 

 are two or three lines in height, and often invest the whole surface of 

 the plant on which it grows. 



3. L . jlabelldta, Ag. (flabellate Licmophora); densely tufted, 

 when dry green and glistening, stipes elongated very much 



