1875.] DR. J. S. BOWERBANK ON THE SPONGIAD. 281 
the dermal rete with its central canals, and the smooth elongate-coniecal 
defensive organs, x 36 linear. 
Fig. 7. A small portion of the siliceo-fibrous skeleton of Farrea parasitica, 
x 80 linear. 
2. Contributions to a General History of the Spongiade. 
By J. S. Bowrrsann, LL.D., F.R.S., &e.—Part VII. 
[Received March 12, 1875.] 
When my friend Commodore Parish went out to China to take 
the command at Hong Kong, he kindly promised to render me any 
assistance in his power in the collection of Sponges and other speci- 
mens of natural history; and I am pleased to say he has performed 
his promise in a most effective and liberal manner. By far the 
greater number of specimens of Sponges sent home to England are 
so carefully and effectually washed instead of being dried immedi- 
ately in the condition in which they come from the sea, that the 
greater portion of their most valuable specific characters are com- 
pletely destroyed. This destructive process has been carefully 
avoided in the preservation of the specimens which form the subjects 
of the present communication ; and the descriptions of these speci- 
mens are the more valuable to science as they lead us to the 
conclusion that the species at that distant portion of the earth are 
in reality very closely allied in their generic and other anatomical 
characters to those of our Northern European seas. 
Microciona TUBEROSA, Bowerbank. 
Sponge massive, sessile, tuberous; tuberous projections corrugated, 
minutely spinous, more or less fistulous. Oscula simple, small, 
dispersed. Pores inconspicuous. Dermal membrane pellucid, spi- 
culous; tension-spicula acuate, slender, dispersed, rather few in 
number. Skeleton-columns rather stout, anastomosing, forming a 
coarse, open, aud somewhat complicated rete; skeleton-spicula acuate, 
rather long and slender ; internal defensive spicula attenuato-acuate, 
small, entirely spinous. Interstitial membranes spiculous ; tension- 
spicula slender, acuate, few in number. 
Colour, in the dried state, dull pale green. 
Hab. Straits of Malacca (Commodore Parish, R.N.). 
Examined in the dried state. 
This very remarkable sponge was sent to me by my friend Com- 
modore Parish with several other interesting and valuable specimens 
collected in the Straits of Malacca. It is based on the surface of 
another species of sponge, a unispiculous Halichondria, which it 
almost entirely covers, and with which it is so intimately incorporated, 
and so closely resembles it in colour, as to render it very difficult to 
discriminate the two without a microscopical examination of their 
structures. Its external form is singular and very characteristic. 
It is 23 inches long, 14 broad, 1} inch in height; and its external 
