42 CELLULARIID^. 



probably the remains of the vibracular cell. It still 

 retains the general form of the latter^ but has lost its 

 distinctive strcuture. In Cellularia all trace of it has 

 disappeared with the exception of the pores from which 

 the radiciform fibres originate^ and which are present on 

 every cell. 



M. ternata sometimes attains the height of an inch or 

 more, but is generally of smaller size. 



Menipea Jeffreysii, Norman. 



Plate IX. figs. 1, 2. 



Menipea 3 effk^^su, Norman, Quart. Journ. Micr. Sc. 1868, (n. s.) viii. 213, 

 pi. V. figs. 4-8 *. 



Zoarium dichotomously branched ; internodes short (4-7 

 cells). Zooecia biserial, alternate, elongated and nar- 

 rowed below ; aperture regularly oval, margin a little 

 raised, with 3 (or 4) spines at the top ; operculum 

 entire. Lateral avicularia small and inconspicuous, 

 placed immediately below the spines ; on the front of 

 the cell below the aperture, a raised avicidarium, with 

 pointed mandible, directed downwards. Omcia sub- 

 globose, smooth. 



Locality. Shetland (C. W. Peach). A few minute frag- 

 ments only were obtained, among sand dredged in Shet- 

 land by Mr. Jeffi'eys and Mr. Norman. 



We know nothing as yet of the size or general habit of 

 this species. The diagnosis is founded on a mere frag- 

 ment kindly lent me by Mr. Norman. There is nothing 

 very marked in the minute characters; the raised and 

 prominent avicularium at the base of the aperture is per- 

 haps the most striking feature. 



I have found it difficult to determine the exact number 

 of the spines, from the condition of the specimen ; but it 



* In fig. 8 the operculum is erroneously represented as lobed. 



