NO. 2 OSBURN: eastern pacific BRYOZOA CHEILOSTOMATA 381 



The characters mentioned appear only slight for the separation of 

 a new species but the cribrate covering of the ascopore is very definite 

 and I have not been able to find any evidence of intergradation with the 

 usual form of ascopore in other species. Spinules are present in several 

 other species, both on the distal projection and around the inner border, 

 but they never appear to fuse to form rounded pores over the whole 

 area as they do in cribrosa. The smaller zooecia with larger and less 

 embedded ovicells also separate it from californica. It should be noted 

 that in dead specimens with the ectocyst removed, the cribroid plate is 

 usually lost and the ascopore resembles that of californica except that it is 

 much larger. 



Type, AHF no. 80. 



Type locality, Corona del Mar, Newport Harbor, southern Cali- 

 fornia, growing on algae attached to the piles of docks. Occurring com- 

 monly alongshore from Mussel Point, northern Cahfornia (A. E. Blagg, 

 collector) southward to Tomales Bay, Monterey Bay, Santa Barbara, 

 San Pedro Harbor, Newport Harbor to San Diego Bay, California. 

 Dredged by the Albatross, Sta. D 2945 near Anacapa Island, southern 

 California at 30 fms, and by Dr. C. L. Hubbs at Guadalupe Island off 

 Lower California at 40 fms. 



Microporella californica (Busk), 1856 



Plate 44, fig. 2 



Lepralia californica Busk, 1856:310. 

 Microporella ciliata form californica, Hincks, 1883 :444. 

 IMicroporella californica, Robertson, 1908:281, (part). 

 Microporella californica, O'Donoghue, 1923 :32 ; 1926 :65. 

 Microporella californica, Canu and Bassler, 1923 :123. 



"Cells broadly oval, surface minutely punctured; a lunate pore in 

 front, a little below the mouth; an avicularium on either side above. 

 Mouth rounded above, lower lip straight, four superior spines. Ovicell 

 small, sub-immersed. Hab. California, Dr. Gould." 



The above is Busk's brief description. His figure (plate 11, figs. 6 

 and 7) represents the species very well, except that his artist appears to 

 have added a row of tremopores distal to the ascopore. The lunate 

 opening of the ascopore, as shown by Busk, is correct. 



The related form described by Robertson as californica is quite simi- 

 lar in most respects, but has the ascopore closed by a "sieve plate" with 

 small round pores instead of having the usual lunate slit (see M. 

 cribrosa, new species). Otherwise Robertson's description applies equally 

 well to both forms. 



