298 General History of the Marine Polyzoa. 



bifid denticle) a central mucro, bearing on the top a minute 

 avicularium, commonly two or three slender spinous processes 

 below it on the cell-wall, also aviculiferous ; at the top of the 

 cell on each side a rather stout 3 calcareous, cylindrical pro- 

 cess, with a minute avicularium on the summit ; on one side 

 of the orifice a very large raised avicularium, with spatulate 

 mandible directed obliquely downwards. Oo&cium wider than 

 high, well rounded above, the sides slightly incurved and 

 prolonged below alongside the oral arch, which is wide and 

 shallow, the surface of a delicate silvery whiteness, covered 

 with extremely minute risings, closely packed together. 



Loc. Singapore or Philippines (Miss Jelly). 



The most remarkable characteristic of this species is the 

 profusion of the avicularia, and not only their profusion, but 

 their peculiar character. With the exception of the large 

 spatulate form, which occurs singly on a great proportion of 

 the cells, they are all minute in size and mounted on the top 

 of a calcareous column or erect spine-like process, and are 

 present in extraordinary abundance. 



EXPLANATION OF THE PLATES. 

 Plate VI. 



Fig. 1. Flustra spinuligera, sp. n. a. Segment of the zoarium, uat. size. 



b. Abnormal zooecium. c. Avicularium. d. Avicularium of 



Flustra denticulata, var. inermis, Busk *. 

 Fig. 2. Schizoporella concinna, sp. n. a. Orifice and lateral avicularia. 

 Fig. 3. Schizoporella bimunita, sp. n. a. Ocecial cells. 

 Fig. 4. Schizoporella scabra, sp. n. 

 Fig. 5. Flustra nobilis, sp. n. a. Avicularia. b. Zooecium, showing the 



origin of the radical fibres at a. 

 Fig. 6. Schizoporella pectinata, Busk, form Africana, nov. 



Plate VII. 



Fig. 1. Schizoporella spectabilis, sp. n. a. Ooecium. 



Fig. 2. Mucronella aviculifera, sp. n. 



Fig. 3. Schizoporella inconspicua, sp. n. 



Fig. 4. Lepralia ocellata, sp. n. a. Orifice. 



Fig. 5. Membranipora ebumea, sp. n. 



Fig. 6. Lepralia laneifera, sp. n. a. Group of zocecia with ooecium. 

 b. Ooecium, with penthouse-like projection in front. 



* After the figure in the ' Challenger ' Report, pi. xxxii. fig. 2 c. 



