478 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



neeted by intermediates. The connectives vary also as regards rich- 

 ness of development; sometimes sparsely and regularly developed, 

 the resulting net work coarse and ladder-like, with meshes that are 

 often about 2 mm. wide (18796, pi. 7, fig. 6) ; or again so richly de- 

 veloped as to form a network as close as in Euspongia officinalis; 

 intermediates connect these extremes. 



Schulze's account makes it plain that Sjiongelia pallescens can 

 not be split up into distinct subgroups. The different forms to 

 which he gives the names of subspecies and variety are, as he says 

 (p. 149), only types within the species and not subdivisions. These 

 types he regards (but here he is, one suspects, only in part on solid 

 ground) as forms which owe their differential peculiarities to the 

 local environment. With this understanding, Schulze makes two 

 subspecies, fragilis and elastica. In fragilis not only the main fibers 

 but the connectives, which are usually sparsely developed, contain 

 abundant foreign bodies. Within this subspecies the body may be 

 incrusting, or growing up into branches, the branches in some speci- 

 mens tubular, in others solid. Such types (formae in our current 

 terminology) he distinguishes as varieties incrustans, tubulosa, and 

 ramosa. In the other subspecies, S. pallescens elastica* the connectives 

 for the most part are without foreign particles and form well-de- 

 veloped reticula. In this subspecies the body may be massive (var. 

 massa) or more or less branched, the branches generally solid (var. 

 lobosa.) A tendency is noted for differential color characteristics to 

 be associated with the structural subspecific characters. 



Lendenfeld (1889) separated Schulze's two subspecies as distinct 

 species. S. fragilis and $. elastica, but the facts stated above would 

 seem to show that the separation is artificial and that the single species 

 should be maintained in Schulze's sense. Schmidt's name of pal- 

 lescens (1862) employed by Schulze must, however, give place to 

 fragilis, since Lendenfeld has shown (1889, p. 642) by direct com- 

 parison that Dysidea fragilis (Montagu, 1818) Johnston. 1842, is 

 identical with Schulze's subspecies fragilis. The name of the species, 

 conceived in Schulze's sense, thus becomes S. fragilis (Montagu). 

 I suggest that elastica be set off as a variety. The Philippine sponge 

 may be set off as another variety, fasciculata, distinguished by the 

 fascicular character of the main fibers. It approaches the type in 

 that the connectives contain foreign particles, elastica in that they 

 are richly developed. Doubtless with continued study other combi- 

 nations — as, for instance, fascicled main fibers with sparsely or richly 

 developed connectives free from foreign particles — will be dis- 

 covered. As numerous combinations of characters come to be known 

 within a group ("species'") which can not actually be split into 



