APPE>fDIX. 395 



The two lateral teeth are long, acute, and slightly everted ; 

 the upper third tooth is sharp, but not near as long as the 

 others; the border of the mouth is as it were excavated 

 below, so that the mouth is as nearly as possible vertical. 

 Contrary to what is the case iu S. divergens, but exactly as 

 is represented in Savigny's figures of the so-caUed S. 

 disticha (Egypt, pi. 14. fig. 2, 3.); and S. distans (Egypt, 

 pi. 14. fig. 1, 3.) the lateral teeth are sloped or bevelled 

 ofi' from below upwards, and not from above downwards, 

 as in S. divergens (Mihi.) 



2. Pasythea, Lamoroux. 

 Cells in distinct sets, at some distance apart. 



1 . P. hexodon, n. sp. 



Cells in sets of six, — three on each side ; a single axillary 

 ceU in each dichotomous division of the polypidom. OviceU 

 pedunculate ovoid, adnate to the rachis, with a lateral 

 opening. 



Hab. — Off Cumberland Isles, 2? fathoms. 



As this difiers in the number of cells in each set, as well 

 as in the form of the cells, and in the form and position of 

 the oviceU, it appears irreconcHeable with Lamouroux's 

 p. quadridentata. According to the figure given of the 

 latter the oviceU is not adnate, and is spirally grooved. 



3. Plumulakia, Lamarck. 



a. Angiocarpese — ovicells enclosed in sUiquose, costate 

 receptacles. 



1 . P. Huxleyi, n. sp. 



Plumularia — Huxley, Philos. Trans. Part II., 1849, 

 p. 427. pl- 39. figs. 43 and 45. 



Cells cup-shaped, shallow ; mouth nearly vertical, sub- 

 quadrangular, margin subcrenate, plicate ; with a small 

 acute central denticle in front, and a wide shallow notch 

 behind. Rostrum twice as long as the cell, arising from 



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