THE NAUTILUS. 47 



rower aperture and less prominent plait on colu- 

 mella." 



Pilsbry. Tornatina carinata Cpr. "Resembles T. infrequens 

 C. B. Ad. more than T. cerealis Old." 



These notes would indicate a close similarity between at 

 least several of the species, but a distinction between culcitella 

 and cerealis which would make Dr. Ball's statement that the 

 latter is a junior form, of the former to seem very doubtful. 



One species of Acteocina is occasionally found on the mud 

 flats of southern California bays in considerable numbers. 

 The shells average about 4 mm in length and are of the char- 

 acteristic shape of the genus, but the rather flat apex is always 

 more or less eroded and pitted. These have been identified as 

 A. inculta Grid. The description of this species calls for an 

 ivory-white shell. As found by the writer, they are colored 

 to varying extents with a brownish ferruginous stain. These 

 are found traveling just under the surface of the mud and 

 their presence is shown by a trail very similar to that of a 

 small Olivella. Like the Olivellas, a large number are always 

 found traveling together. 



Associated with the last few specimens of a quite different 

 and slightly larger species are sometimes found. Under a 

 hand-glass the brownish surface is seen to be covered with 

 very fine, slightly undulating spiral lines. The shoulders of 

 the whorls are sharply keeled, so that in looking down on the 

 apex the suture has the appearance of a deep spiral groove. 

 The shores of a large tide pool just inside the entrance to 

 Newport Bay has furnished Southern California collectors 

 with a considerable number of specimens of a large Acteocina 

 which has always been classed as A. culcitella Gld. These 

 vary from 10 to 20 mm. in length but otherwise are very 

 similar to the previously mentioned form. The microscopic 

 brown spiral lines are quite distinct on the under side of the 

 shell next to the aperture, but on the opposite side are very 

 faint, leaving the shell almost white. It is quite probable 

 that the color has been worn off the portion of the shell which 

 is not protected by the mantle of the animal when burrowing 



