94 University of California Publications in Zoology [ VoL - 23 



Somewhat similar relations are shown between the dredge hauls 

 in the various divisions of the bay, but they are much less reliable 

 owing to employment of several different types of collecting apparatus, 

 i.e., boat dredge, beam trawl, sledge trawl, and bucket dredge. Con- 

 sidering only the dredging stations, fifty or more specimens were 

 returned by nine (45%) of the upper bay stations; by eight (53%) 

 of the lower bay stations; by fourteen (27%) of the middle bay 

 stations, of which all but one (93%) are in the upper and eastern 

 portions; and by three (37%) of the outside stations. 



At only two of the dredging stations did the depth exceed 19 

 fathoms : D 5742 in Raccoon Strait, 20 to 30 fathoms (thirty-five 

 specimens) ; and D 5808 in Golden Gate, 27 to 43 fathoms (two speci- 

 mens). Outside, however, no specimens were taken at a depth exceed- 

 ing 14 fathoms. 



The ranges of temperature and salinity as observed for the entire 

 bay, as in the case of Crago nigricauda, are applicable to this species 

 also ; but it must be remembered that the occurrence of Crago fran- 

 ciscorum in Napa Creek, above Mare Island, as well as in Suisun Bay, 

 indicates a range of salinity much below any recorded during the 

 survey. Unfortunately we are unable to cite this range here as no 

 hydrographic observations were made above Carquinez Strait. 



The list of stations at which Crago franci-scoriim was taken includes : 

 D 5700, 5702, 5705-5716, 5719-5721, 5723, 5725, 5726, 5729-5733, 

 5735-5737, 5739, 5741-5761, 5763, 5764, 5766-5768, 5771-5773, 5777, 

 5779, 5780, 5784, 5793-5800, 5802-5808, 5815-5828, 5830, 5847, 5848 ; 

 H 4986, 4987, 4989, 4993-4996, 4998, 4999, 5002-5008, 5010, 5012- 

 5017, 5082-5096, 5098, 5101-5107, 5109-5117, 5120, 5122-5128, 5131, 

 5134, 5137, 5138, 5143, 5144, 5146, 5149, 5150, 5155, 5156, 5158-5169, 

 5171-5173, 5176, 5178-5183, 5185-5188, 5190, 5193, 5196, 5199, 5200, 

 5218, 5228, 5250-5255, 5257, 5262, 5266, 5267, 5269-5276, 5288, 5298, 

 5299, 5302, 5306, 5308, 5311, 5313, 5315, 5316, 5319, 5320, 5330; 

 North of Key Route pier, August 2, 1912 ; Fort Baker, April 19, 1913 ; 

 Tiburon, April 29, 1913 ; electric light, ship 's side, Sausalito, April 3, 

 1913. 



