332 



FUNAFUTI ATOLL. 



HIPPOSPONGIA DURA, Lendenfeld. 



Hippospongia dura, Lendenfeld, Mon. Horny Sponges, 1889, 

 p. 298, pi. 17, fig 15. 



There are five pieces, all of which appear to have been cut from 

 one large specimen. The sponge evidently formed a cake-shaped 

 mass ; it consists of stout lamellae joined at various points, both 

 vertically and at the surface, with a number of subcylindrical or 

 long, narrow meandering lacunae between. 



The dermal membrane is continued over the whole surface of 

 the sponge. Groups of from 20 to 30 oscula pores occur in the 

 membrane overlying the lacunae, the pores vary in shape from 

 round to oval, and are from 1 to 3 mm. in diameter. 



Isolated reticulate patches, with small inhalent pores, exist on 

 the elevated parts of the surface chiefly between the conuli ; the 

 rest of the surface is smooth and imperf orate. The general sur- 

 face is uneven and conulose ; the conuli are variable in height and 

 in their relative distance apart. They are all more or less con- 

 nected by low intervening ridges, and usually about 3 mm. high, 

 and about the same distance from each other, especially on the 

 marginal and elevated regions ; elsewhere they are low and widely 

 separated. 



The skeleton consists of a dense network of uniform fibres, 

 entirely free from foreign bodies ; they are scarcely separable into 

 main and secondaries, and measure from 0*015 to 0'02 mm. in 

 diameter. 



In the denser parts of the sponge the fibres are arranged in 

 trellis-like clusters, the mesh is elongate, angular, rarely with 

 rounded corners ; the fibres at their points of union are not per- 

 ceptably dilated, but retain their cylindrical form. 



In the lagoon with Sarcophyta. 



This species has hitherto only been recorded from the American 

 coast of the North Atlantic. 



FAMILY SPONGELID^. 



SPONGELIA FRAGILIS, var. IRREGULARIS, Lendenfeld. 

 Spongelia fragilis, var. irregularis, Lendenfeld, Mon. Horny 



Sponges, 1889, p. 662, pi. xxxvii., fig. 10. 



This species is represented by several examples in a much 

 broken condition. 



Colour in spirit, yellowish-gray. 



Occupying crevices in dead and honeycombed blocks of coral, 

 on the lagoon reefs. 



I owe the accompanying illustrations to my colleague, Mr. Edgar 

 R. "Waite, from whose careful drawings they have been reproduced. 



