1921] Schmitt: The Marine Decapod Crustacea of California 295 
burrowing forms, which, though not found in company, were taken 
only from sandy beaches: 
Emerita analoga was dug out of the beach skirting the Presidio, west of 
Fort Point, and brought up in the seine both at Fort Baker and o 
Angel Island. 
Upogebia pugettensis was obtained both at Sausalito and at Tiburon; at 
the latter place by means of the seine, 
The other five are all primarily inhabitants of rocky beaches: 
Oedignathus inermis, at Point Bonita. 
Petrolisthes cinctipes, at Sausalito, and along the Richmond shore. 
Pagurus samuelis, along the Richmond shore. 
Pachygrapsus crassipes, on the Presidio shore near Fort Point, at Point 
Bonita, at Sausalito, and on Red Rock. 
Hemigrapsus nudus, on the Presidio shore near Fort Point, at Point Bonita, 
at Sausalito, north of the Key Route Pier, along the Richmond shore, 
and on Red Rock. 
The other sixteen bay species grouped on the basis of their dis- 
tribution within the bay, arrange themselves as follows: 
a. Ten, restricted to the middle bay: 
Pandalus danae Crago munitella 
Spirontocaris franciscana Epialtus productus 
Spirontocaris paludicola Cancer antennarius 
Spirontocaris brevirostris Pinnixa littoralis 
Spirontocaris taylort Scleroplax granulata 
b. One, found only in the middle and the lower bay. 
Cancer productus. ~ 
c. Five, common to all three divisions of the bay: 
Callianassa longimana Pinnixa schmitti 
Pagurus hirsutiusculus Hemigrapsus oregonensis 
Pinnixa franciscana 
a. Excepting the first, third and ninth, seven of the ten species 
found only in the middle bay, inclusive of shore stations, are re- 
stricted wholly to that portion lying west of a line drawn across the 
head of Raccoon Strait, and from Blunt Point on Angel Island to 
the nearest point on the San Francisco shore. 
This limitation of range seems to be closely correlated with the 
character of the bottom, which within that area is more or less hard, 
rocky, gravelly, or sandy with very little if any admixture of mud, 
exclusive, of course, of the muddy portion of Richardson Bay, where 
only two hauls of the boat dredge were made and none of the strictly 
middle bay species was found. 
