Vol. XI] BERRY— FOSSIL CHITONS 413 



vious workers. 8 It is situated in the sea cliff about half way 

 of the peninsula on the western or ocean side. After revisiting 

 the locality at my request, Mr. Stephens writes under date of 

 June 5, 1918: "The bed containing the fossil shells lies un- 

 conformably on the strata containing the lignite, and is of 

 much later age. Only fragments of the fossil bed are left as 

 the sea is wearing the cliff away." He failed to find any 

 further chitons, but the following had been secured previously : 



Mopalia muscosa (Gould) 

 Cryptochiton stelleri (Middendorff) 

 Ischnochiton conspicuus Carpenter 



acrior Carpenter 

 Callisto chiton crassicostatus Pilsbry 



Cryptochiton stelleri and Acmcea mitra seem to be adventi- 

 tious northern elements, the presence of which is not at first 

 glance easy to understand, as the aspect of the remaining fauna 

 is decidedly southern. For the latter reason I correlate the ex- 

 posure with the Upper San Pedro, although the faunal list 

 finds no complete parallel in that of any of the previously de- 

 scribed horizons. 



17. Along the sea cliff between one and two miles north of 

 Point Loma and Ocean Beach, San Diego County, California 

 (Cal. Acad. Sci. Loc. 108). 



"The fossils were obtained from coarse sand and gravel 

 which occurs just above the contact between the cretaceous ( ?) 

 and the overlying late formation. The fossils occur about 50 

 ft. from the water. The formation in which they occur is al- 

 most horizontal." 



3 The full list of species identified other than the chitons listed above seems worthy 

 of record, so is appended here.: 

 Acmcea scabra Gould {^spectrum Nuttall) Thais cf. emarginata (Deshayes) 



" mitra Eschscholtz Acanthina lugubris (Sowerby) 



Fi-ssurella volcano Reeve Alectrion cooperi (Forbes) 



Diadora aspera (Eschscholtz) Gadinia reticulata Sowerby 



Haliotis cracherodii Leach Pecton (Plagioctenium) circularis Sow- 

 Tegula (Chlorostoma) funebralis (A. erby (aequisulcatus Carpenter) 



Adams) Hinnites giganteus Gray 



Tegula (Chlorostoma) sp. Septifer bifurcatus (Conrad) 



Norrissia norrissii (Sowerby) Cardita subquadrata Carpenter 



Astraa undosa (Wood) Chama exogyra Conrad 



Crepidula aculeata Gmelin Phacoides californicus (Conrad) 



" cf. lessonii Broderip and Petricola cardttoides Conrad 



explanata Gould Cumingia lamellosa Sowerby 



Hipponix tumens Carpenter Saxicava sp. 



" cf. cranioides Carpenter Pholad sp. 



Littorina scutulata Gould Cancer productus Randall 



" planaxis Philippi Tetraclita rubescens Darwin 

 Cerithidea sacrata Gould 



