486 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



The ovicell is located at or near the base of the peristome, and on 

 complete calcification may be partially embedded; it measures about 

 0.24 mm wide and has the characteristic finely perforated, semicircular 

 frontal area. 



There is a remarkable difference in appearance between the young 

 zooecia with their long peristomes and the heavily calcified old ones in 

 which the tremocyst covers the peristomes nearly to the tips, and old 

 colonies encrusting stones are often scarcely recognizable except at the 

 growing edges. 



Hincks and Robertson both confused this species with L. spinulosa, 

 though there is much difference in the size of the zooecia and the nature 

 of the peristomes. Canu and Bassler located the species properly under 

 Gabb and Horn's E. punctulata, but misplaced it in the genus Tubucel- 

 laria which has an ascopore and flexible joints. Dr. Bassler has kindly 

 reexamined his fossil material and agrees (in litt.) that it belongs in 

 the genus Lagenipora. O'Donoghue separated it from spinulosa and 

 considered it to be a new species, erecta. 



Gabb and Horn described the species from the "Miocene" (later 

 corrected to "Post-Pliocene") of Santa Barbara, California, and Canu 

 and Bassler found it in the Pleistocene of Santa Barbara and Santa 

 Monica. It is quite abundant in the Pleistocene of southern California 

 at various places from Santa Barbara to Newport Harbor, and I have 

 seen numerous fossil specimens which have been dredged near shore and 

 which had been washed out of the shore-wise cliflfs. 



The records of Hincks, O'Donoghue and Robertson indicate distribu- 

 tion from British Columbia to Monterey Bay, California. 



Hancock Stations: occurring at 125 dredging stations, from northern 

 California to the tip of Lower California, the Gulf of California (16 

 stations), and the Galapagos Islands (13 stations). It appears to be 

 most abundant in the southern California region at depths ranging from 

 near shore to about 100 fms. 



Lagenipora mexicana new species 

 Plate 59, figs. 7-8 



Zoarium with a small encrusting base which surrounds stems; erect 

 and irregularly branching, the branches round, not all in one plane ; basal 

 portions of the stems 1.00 to 2.00 mm in diameter, the younger tips 

 0.60 mm. The zooecia are moderate in size, 0.50 to 0.60 mm long by 

 0.35 to 0.40 mm wide ; lageniform, completely decumbent, in younger 

 stages quite distinct, the front inflated with evenly distributed large 



