116 Descriptions of New, 



so closely connected by the present form and D. intermedia 

 that, in my opinion, the species with the (abortive or perfect) 

 avicularia at the summit of the cell ought to be referred to 

 the older genus Beania, while the others might find a place 

 elsewhere. 



Membranipora acifera, n. sp. Fig. 2. 



Cells elongate-quadrate, wider in the middle; aperture 

 occupying the whole front, except a minute corner on each 

 side inferiorly ; margin much raised ; one or two sharp 

 incurved spines on each side, and usually a small round spine 

 at each upper angle ; avicularium in a separate area at the 

 base of a cell, mandible very long and narrow ; ovicell small, 

 immersed in the base of the cell above. 



QueensclifT, a single specimen. 



Membranipora flagellum, n. sp. Fig. 3. 



Cells arranged in regular transverse series, elongate-quad- 

 rate, separated by much-raised margins, the lower fourth 

 filled in by a perforated plate, a little more extensive on one 

 side ; upper margin deeply arched ; two conical stout spines 

 superiorly on each margin common to two adjacent cells ; 

 an enormous whip-like vibracular spine below the aperture 

 on one side, and one or, occasionally, two small spines on the 

 margin of the aperture on the other side. 



Port Phillip Heads, Mr. J. B. Wilson. 



Membranipora papulifera, n. sp. Fig. 9. 



Cells arranged in more or less regular, contiguous lines, 

 narrowed below, oval, very slightly filled in below ; margin 

 thickened, strongly crenulated, the lower part raised into an 

 elevated prominence. 



Port Phillip Heads, Mr. J. B. Wilson. 



Membranipora albispina, n. sp. Fig. 10. 



Cells elongated, narrowed downwards ; aperture occupying 

 upwards of two-thirds of the front, rounded below ; mouth 

 very large ; on each side a series of 3 — 5 enormous, pod-like, 

 white, articulated spines, and generally two or three smaller 

 ones from the upper margin. 



QueensclifT. 



The only species with which this can be confounded is 

 M. ciliata, the spines of which are sometimes of great size, 



