ART. 4 SPONGES OF CALIFORNIA de LAUBENFELS 47 



favorable to the encrusting form that almost every sponge here is 

 encrusting, yet our Tethyas are at least massive and hemispherical. 

 The sponges properly referable to Thnea seem to be merely encrust- 

 ing in whatever part of the world they occur. The typical spicule 

 in Tethya is a fusiform strongyle, which varies toward being a 

 tylostrongyle or style, but is very large, usually around 25ja by 

 2,000ja. The principal TiiThea spicule is a sharp-pointed, large- 

 headed tylostyle, about 10/x by 500/i to 800/t. The principal micro- 

 sclere of Tethya is a very large spheraster, usually about TSjU. in 

 diameter. The asters of Timea are characteristically well under 25,a 

 in diameter. 



Timea as here understood comprises beside T. authla at least the 

 following : 



Hymedes7ma stelJata Bowerbank (1866, p. 150), from Great 

 Britain, with tylostyles about 10/a by 500/x, and strongylasters all 

 about 13|U, in diameter. 



Columnitis squamata Schmidt (1870, p. 25), from the West Indies, 

 with tylostyles and with tylasters, oxyasters, and roughened strongy- 

 lasters. Schmidt gives no spicule measurements but from his figure 

 one can deduce the megascleres are well under a millimeter long. 



Donatia fara^itica Higgin (1877, p. 5), from the West Indies, 

 with tylostyles 7^1 by 500/a, rough tylasters 12/a, and spherasters ( ? ) 

 25/t. 



Timea tetractis Hentschel (1912, p. 322), from the south Pacific 

 with tylostyles up to Ijx by 520/x, strongylasters up to 12/u,, and rough- 

 ened oxyasters with very few rays, 15/x to 31/*. 



Family CLIONIDAE Gray 

 Genus CLIONA Grant 



CLIONA CELATA Grant CALIFORNIANA. new variety 



Holotype.—V.S.'^M. No. 21437 ; B.M. No. 29.8.22.52. 



Type locality. — Pacific Grove, Calif., February 7, 1929, intertidal, 

 boring in the shells of dead barnacles. 



Additional material examined. — ^The species is moderately com- 

 mon in the shells of Haliotis rufescens that are collected near Mon- 

 terey at depths of 1 to 20 meters. 



Description. — Shape, amorphous, boring, making tunnels about 

 1 mm in diameter, and proliferating out of them in masses. Size, 

 the masses are well over 10 mm in diameter. Consistency, mediocre. 

 Color in life, yellow ; preserved, drab. Oscules, minute ; on papillate 

 projections in the boring form. Pores, minute ; on papillate projec- 

 tions in the boring form. Surface, superficially smooth, but not 

 even, very irregular. 



