FAMILY 8TP]r}AN0P0RELLID.^. ' 



Steganoporella, Smitt. 

 S. magnilabris, Busk, sp. Aldinga. 



FAMILY CRIBRILINID.F:. 

 HiANTOPORA, 3IcG. 



IL/erox, McG. 



FAMILY MICROPORELLID^. 

 MiCROPORELLA, Gray. 



M. ciliafa, Linn., sp. 



3L Jfalusii, Aiidouin, sp. 



M. diadenia, McG. Robe. 



" var. longispina, jMcG. Semaphore. 



Adeoxa, Lanix. 

 A. alb Ida, Kirchenpauer, var. avicularis, McG. 



FAMILY BSCHARID.E. 



SCHIZOPORELLA, Hilicks. 



S. JIapIestonei, McG. Figs. 4, 5, and oa. Of this two marked 

 forms occur, which might almost be considered as distinct species. 

 In the typical form the zooecia are rhomboidal, separated by 

 narrow raised margins, the surface shining and perforated. The 

 mouth is arched above, wider than high. The lower lip straight, 

 with a small rounded sinus. The peristome above is slightly 

 thickened. On each side in front, below the mouth, is a small, 

 solid, rounded protubemnce, occasionally wanting. The ooecium 

 is broad, prominent and flattened in front, the upper margin 

 forming a thickened and smooth band, a more or less regular 

 row of white-bordered pores along the inner margin of the band, 

 and others scattered over the anterior surface. The peristome of 

 the ooecial cells is produced as a flat pointed process from each 

 side to meet in the centre, forming an arch over the suboral 

 sinus. The front of the ocecium in perfect specimens is usually 

 of a bright-brown colour, forming a marked contrast to tlie white 

 rim. In others, however, the bright colour is lost. 



I have no doubt this is identical with *S'. liicida, Hincks (Ann. 

 and Mag. Nat. Hist., March, 1885). 



The other form, which may be named var. avicularis, has an 

 elliptical avicularium placed obliquely below or to one side of the 

 oral sinus ; below or supporting the avicularium there is usually 

 a small, irregular, glassy, calcareous mass, extending partly down 

 tlie centre of the cell, and frequently with one or more shining 

 nodules comparable to the two suboral processes in the normal 

 form. The peristome in the barren cells is usually produced on 



