tg2 Laura R. Th()RNRL\' : Report on Marine Polvzoa. [Vol. I, 



regularly punctured. Orifice large, arched above, contracted near 

 the base, with a point there on either side below the hinge of the 

 operculum. Six to eight large, jointed spines above, six of which 

 show in front of the ooecium when present. Peristome rising 

 below the orifice into a swollen hollow process with an avicularium 

 on its inner aspect b^ing horizontally and having a tongue-shaped 

 mandible. Numerous protuberances bearing small, rounded avicu- 

 laria scattered over the front wall of the zooecium and round the 

 margin of the orifice, sometimes reduced to two or three only, 

 OcEcia finely punctured, their sides prolonged downwards, leaving 

 a square opening. 



Locality. — N. Sentinel bearing N. 15 miles, W. 18 miles, 250 fath- 

 oms ; growing on the cast spine of a sea-urchin. 

 There are resemblances between this species and Mucronella 

 vultur and M. aviculifera, but there is the great distinction here of 

 no internal denticle to the orifice. 



64. Mucronella maculata , sp. nov. 



Fig. j.— Mucronella inaculata, sp. nov. 



Zoarium incrusting, loosel}^ attached to sea weed. Zocecia 

 large, distinct, deeply divided. Surface finely granulated. Ori- 

 fice rounded above, narrowing gradually to a point below, usually 

 two spines above, a large mucro below, either in the centre or to one 

 side according to the form of a prominence bearing an avicularium 

 which is usuall}' large and rounded, with a horizontally placed 

 avicularium and occupying a large space rather to one side of the 

 centre of the orifice pushing the mucro to one side ; it is sometimes, 

 however, produced into a narrow, curved process which stands 

 straight up on one side of the orifice, the avicularium long and point- 

 ing upwards. There is sometimes a second similar avicularium 

 on the other side of the orifice. When this form of avicularium 

 is present the mucro holds its central position. A third form of 



