SILICIOUS AND HORNY SPONGES WILSON. 425 



Subfamily Merliinae 



Merliinae Kibkpatrick, 1911, p. 51. 



Silicious sponges which have acquired a basal calcareous skeleton. 

 The silicious sclerites include tylostyles and peculiar microscleres, 

 clavidiscs, probably derived from diancistron-like or sigma-like spi- 

 cules. Other microscleres, rhaphides, trichodragmas, toxas, and 

 sigmas occur in the only known form, Merlia normani. 



Kirkpatrick, 1911, and Dendy, 1921 (p. 51), regard this aberrant 

 sponge as related to the Hamacanthinae, and since they place the 

 latter in the Haploscleridae, the Merliinae are put there too. The 

 relationship to Hamacantha seems to be the basic fact. 



Subfamily Mycalinae 



Esperellinae Ridley and Dendy, 1S87, p. 62. — Dendy, 1905, p. 159. 

 Esperellinae part plus Dendoricinae part, Topsent, 1894c, pp. 6, 9. 

 Mycalinae Lundbeck, 1905, p. 7. — Hentschel, 1911, p. 287. 

 Mycalinae plus Myxillinae part, Topsent. 1913, pp. 625, 632. 



Skeletal fibers, or spicular tracts, without echinating spicules and 

 not markedly areniferous. 



Dendy, 1921b (p. 55), proposes to restore the names Esperella and 

 Aegagropila for genera made to receive certain species which ac- 

 cording to recent usage would fall under Mycale. In consequence 

 he retains the name Esperellinae for the subfamily in place of Mycal- 

 inae. This is a change in a set of terms which seemed about to es- 

 tablish themselves definitely, and if it is desirable, as Dendy points 

 out, to segregate species of Mycale, why not set them off as sub- 

 genera ? 



Genus MYCALE Gray (1868). 



Esperella Authors. 



Mycale Gray, 1868, p. 533.— Thiele, 1903, p. 949 (nomenclatural history 

 here given). — Lundbeck, 1905, p. 23. 



Incrusting massive, and erect forms of various shapes, sometimes 

 with considerable symmetry, occur; the form is rarely tubular. 

 Megascleres combined in polyspicular fibers, usually with but little 

 spongin, but the spiculo-fibers may be well cornified and firmly 

 united in reticular fashion. Megascleres monactinal, stylote to tylo- 

 stylote. The characteristic microscleres are palmate anisochelas; to 

 these may be added sigmas, toxas, trichodragmas, and very small 

 isochelas (possibly young forms of the anisochela), in different com- 

 binations. 



81709—25 11 



