REVISION OF FRESHWATER SPONGES OF SPONGILLIDAE 151 



the revived genus Metania (de Laubenfels, 1936; Burton, 1938 

 Penney, 1960) for the rest. 



The erection of M. lissostrongyla from Africa by Burton (1938) was 

 the result of a wrong translation of Weltner's (1895) German descrip- 

 tion of T. pottsi, which clearly states that the megascleres of the latter 

 species are stout, smooth, and feebly curved amphistrongyla, and not 

 "spined, instead of smooth strongyla" as quoted by Burton. The 

 specific name lissostrongyla, designed to differentiate Burton's species 

 from that of Weltner, is therefore meaningless. 



Morphometric comparisons of ilf. vesparia with both M. pottsi and 

 M. lissostrongyla revealed that these three species must be considered 

 identical, since they display uniform characters in most regards. 

 Some slight and certainly unimportant differences, like the length 

 range of megascleres and the rate of abundance of free microscleres, 

 represent nothing more than ecomorphic variations in distant popula- 

 tions and cannot even be used for racial discrimination. It will be 

 most interesting to find possible distributional bridges between the 

 populations of M. vesparia in Southeast Asia and those in Africa. 

 However, since the Indian spongillids have been studied in great 

 detail, and M. vesparia does not seem to occur on that subcontinent, 

 the distribution of this species must stUl be considered to be discon- 

 tinuous. 



Metania vesparioides (Annandale, 1908) 



Plate 14, figures 13-15 



Tubella vesparioides Annandale, 1908b, p. 157; 1911c, p. 120; 1918a, p. 213. — 

 Gee, 1931e, p. 52; 1932c, p. 42; 1933c, p. 249.— Penney, 1960, p. 59. 



Material. — Slide of type (IM); slides of syntype (N. Gist Gee, 

 and Amst]\l) ; material and slides of syntype (AusAI). 



Description. — Sponge massive and bulbous; surface strongly retic- 

 ulate and hispid, due to projection of radiating spicule fibers through 

 dermal membrane; dermal membrane closely adhering to symplasm. 

 Skeleton consisting of strong radial spicule fibers, and slightly slimmer 

 transverse fibers; both forming a rigid and compact network of open 

 meshes. Consistency of dry sponge firm but brittle. 



Megascleres stout, fusiform, slightly curved, and smooth amphioxea 

 of rather uniform length; length range 300-325 n, width range 12-15 fi. 



Microscleres almost straight, fusiform, and sharply pointed am- 

 phioxea, covered with small granules at their tips, and bearing nu- 

 merous larger spines in their central portion; length range 68-75 M, 

 width range 2-3 M. 



Gemmoscleres tubeUiform, lower rotule often irregular or polygonal 

 and ^vith shghtly recurved margin, which as a rule is entire; radial 



