Data on the bathymetric occurrence of the modern molluscan fauna of southeastern Alaska are scant. The nearest area with at all detailed bathymetric range data is the Puget Sound area of southernmost British Columbia. Data from the Puget Sound may not be strictly applicable to the more northern and possibly cooler-water late Pleistocene? Assemblages from the Juneau area but they are all that we have to work with. The problem is that certain cool water species that live intertidally or in very shallow water in the northern part of their ranges are known to inhabit progressively deeper water toward the south. This may not be a problem in this case as the protected coast environments of the two areas in question have comparable surface water temperatures. (However, out coast temperatures are significantly cooler at the latitude of Juneau than off southern British Columbia).

With these qualifications in mind, the collections seem to fall in two groups. The first group (Sta. 87 and Sta. 151) is of a more shallow aspect than the other. The few species present are commonly found living intertidally or at very shallow inner sublittoral depths (low tide to about 10 fathoms). A second group consisting of collections from Station 104, 149, and 215 probably represent a single community. Several of the species have been dredged from depths of 25 fathoms or deeper in the Puget Sound area. A bathymetric environment of 20 to 25 fathoms or possibly somewhat deeper is suggested by this association.