FRILLED SPONGE.

A species not infrequently dredged up by the pearl-shell fishers in Sharks Bay, Western Australia.

Photo by W. Saville-Kent, F.Z.S., Milford-on-Sea.

RETICULATED SPONGE.

The skeleton of this sponge is composed of fine horny fibres resembling those of ordinary commercial sponges.

Among the more remarkable sponges may be mentioned the Neptune's-cup Sponge, like a huge chalice 3 or 4 feet high, indigenous to the South Seas; the wonderful cornucopia-shaped Lace-sponge, consisting of a lace-like reticulation of flinty fibres; and its near ally the Glass-rope Sponge, forming a cup- or bird's-nest-shaped body, supported on a long cylindrical stalk of flinty fibres that may be over a foot in height. One of the compound or social sea-anemones is in the habit of forming bark-like encrustations on this glassy stem, and it was for a long time doubtful whether the sea-anemone or the sponge produced the supporting-stalk.

Photo by W. Saville-Kent, F.Z.S., Milford-on-Sea.

PORTUGUESE BIRD'S-NEST SPONGE.