AET. 4 SPONGES OF CALIFORNIA de LAUBENFELS 81 



the tAYo. The resemblance to Lambe's sponge is not complete, but 

 it is still so great that I hesitate to create a new species when 

 the geographical location is so close. The principal spicules of the 

 Canadian sponge range somewhat larger, and it has a distinct 

 category of very short acanthostyles that I do not find in the Cali- 

 fornia specimens. Lambe's description mentions no sigmas more 

 than 26/M. Aside from these items the agreement is very close. This 

 species is rather close to Myxilla rosacea Lieberkiihn, which is the 

 type species of the genus, a Mediterranean form. 



On May 11, 1929, I collected a sponge near Pacific Grove, Calif., 

 that had the megascleres and all the characteristics of M. parasitica, 

 but no microscleres. The literature contains very few references to 

 myxillalike sponges without microscleres (see notes under Myxilla 

 vers^icolo7') , so this occurrence is most remarkable. As M. jjarasitica 

 is probably common in the vicinity, I liesitate to create a new species 

 for this form, but hazard a guess that it was an aberrant growth of 

 M. paralitica. It was crowded with embryos, ovoid in shape, about 

 200/i in diameter. 



MYXILLA VERSICOLOR Topsent CALIFORNIANA, new variety 



Holotype.—V.^.'^M. No. 21474; B.M. No. 29.8.22.20. 



Type locality. — Lagima Beach, Calif., intertidal, March 14, 1926, 

 collected by me. 



Description. — Shape, amorphous. Size, 15 mm thick, 5 cm in 

 diameter. Consistency, fragile. Color in life and when preserved, 

 pale drab. Oscules, not evident. Pores, not evident. Surface, 

 superficially tuberculate. 



Ectosomal specialization, a dermal membrane; \Qvy easily de- 

 tachable, fleshy, containing abundant tangent tylostrongyles. En- 

 dosomal stmcture, collenchymatous, with spicules in tracts and 

 others in confusion. Histological details : About 90/x below the sur- 

 face was a layer of very dark cells, which may have been algae. 

 Principal, or ascending, fibers about 40/x in diameter, cored by 

 abundant styles. 



Principal spicules, smooth tylostyles (fig. 46, 5) ; size, 8/x by 265]n 

 to 12/x by 250/A. There are also a few acanthostyles about T/x by 150ju, 

 (fig. 46, A). Ectosomal spicules, tylostrong3des (fig. 46, Z>, E) \ 

 size, 4jLi by 240/x to Sju, by 235^^. Interstitial spicules, tylostrongyles, 

 just like the dermal, are found also scattered through the flesh. 



Remarks. — The nearest relative of this form seems to be Myxilla 

 versicolor Topsent (1893, p. xli), from Banyuls, France (on the 

 Mediterranean coast), which differs in having much larger (400/x) 

 endosomal tylostyles, more so and more usually spined, and in show- 

 ing a variety of colors not yet found in the Californian form. 

 107704—32 6 



