1877.] FIVE NEW SPECIES OF SPONGES. 457 



Colour, in the dried state, nut-brown. 



Hab. Kordo, Island of Mysore, Geelvinks Bay, New Guinea 

 (Dr. A. B. Meyer). 



Examined in the dried state. 



Type in the Dresden Museum. 



Dr. Meyer observes : — " In life, of the gayest green, red, and yel- 

 low colours, which fade away very quickly. 



The form of this sponge is that of a single long fistulous body 

 which has apparently been attached to the side of a mass of calcareous 

 matter by a short stout pedicel, and has then curved upwards to 

 about eight inches in height. Its external diameter rather exceeds two 

 inches ; and its internal one averages one and a half inch. Extern- 

 ally it is very rugged and prominently tuberculous, while its inner 

 surface is smooth and even, with numerous dispersed oscula for 

 discharging their effete streams into the large cloacal cavity, which 

 exceeds seven inches in depth. 



The oscula within the great cloacal cavity are numerous, and ap- 

 pear to be equally distributed throughout the whole of its length ; 

 they rarely exceed a line in diameter. 



The external surface of the sponge abounds in porous cavities or 

 depressions ; but the true inhalant pores of the dermal membrane 

 that lines them are inconspicuous, and I did not detect a single open 

 one on any part of the dermal membrane when mounted in Canada 

 balsam. The dermal membrane is abundantly spiculous. The ten- 

 sion-spicula are acuate, stout and long, and as large as those of the 

 skeleton ; they are dispersed or subfasciculated ; occasionally, but 

 rarely, a few of the attenuato-acuate internal defensive spicula occur 

 among them ; but I could not detect any acerate spicula. The bi- 

 dentate equianchorate retentive spicula are very slender and minute, 

 their denticuli are long and obtusely terminated ; they vary greatly 

 in size, the smallest ones frequently not exceeding half the size of the 

 larger ones. The largest I found measured js'^-ij inch in length ; 

 of the smaller ones, one measured 21V7" inch, and another ^-jj^ inch 

 in length. The fibre of the dermal rete is not so abundantly spicu- 

 lous as that of the skeleton. The latter frequently assumes quite 

 the appearance of a Desmacidon from the abundance of its spicula. 



The skeleton-spicula are of two forms, acuate and acerate, the 

 latter form being of rather rare occurrence ; both forms are rather 

 variable in length : they are very numerous and closely packed in 

 the fibres ; their average length is j-1^ inch. 



The internal defensive spicula are based on the surface of the ske- 

 leton-fibre, from which they are projected at various angles. Their 

 bases and the distal halves of their shafts are abundantly spinous, 

 the proximal half of the shaft being frequently destitute of spines ; 

 these organs are well developed and are all acutely conical. The 

 internal defensive spicula are very numerous, and they form a most 

 effective defence against any minute Annelids that might attempt to 

 enter the skelton structures of the sponge. Their average length is 



The interstitial membranes closely resemble the dermal one, but 



