1918] Packard: Quantitative Analysis of Molluscan Fauna 305 
prising, then, that Macoma balthica and Mytilus edulis have a general 
distribution within San Francisco Bay, when the same species are 
able to endure the rigors of the littoral zone of the North Sea, north 
Atlantic Coast, and western coast of North America. Thais lamellosa 
and Zirfaea gabbi also have wide ranges on the West Coast and are 
closely related to if not identical to Atlantic Coast species. 
TABLE 1 
COMPLETE RECORD OF THE QUANTITATIVE HAULS 
ns un] n n AG: wn L 
t we And we £ a Pane Paar) a wend wend 
ee SAGER dat ca ~ ee ER ea: Soe 
Eve Seo 85 aeens She es pay = B3e 255 
aes Hee 8e Hees Bos Hes $0 9) Bees Bes 
3% 5am yp oo i yale! ea ae yz? Daa 
D5815 A 2 2 2 6 0 6 2 0 
D 5815 B 1 1 0 0 3 3 1 0 
D 5816 A 0 0 0 0 0 0 0 0 
D 5816 B 2 2 2 5 2 7 2 0 
D 5817 A 3 3 1 8 109 117 3 0 
D 5817 B 3 3 3 4 15 19 2 1 
D 5818 A 3 3 al 1 18 19 3 0 
D 5818 B 4 4 1 10 39 49 4 0 
D 5819 A 4 3 3 10 5 15 4 0 
D5819B 1 1 1 3 4 Ul 1 0 
D 5820 A + 3 2 2 5 cf 4 0 
D 5820 B 1 1 0 0 9 9 1 0 
D 5821 A 5 5 4 31 LT, 48 4 1 
D 5821 B 11 11 2 3 37 40 10 1 
D 5822 A 3 3 1 1 224 225 3 0 
D 5822 B 6 6 2 115 83 198 5 1 
D 5823 A 6 6 2 17 91 108 5 1 
D 5823 B 3 3 3 13 2 15 3 0 
D 5824 A 3 3 2 7 24 31 3 0 
D 5824 B 11 10 3 404 2,566 2,970 8 3 
D 5825 A 13 12 uf 1,66 193 359 9 4 
D 5825 B 9 8 1 1 189 190 8 1 
D 5826 A 10 9 0 0 343 343 8 2 
D 5826 B 10 9 2 33 126 159 8 2 
D 5827 A 11 10 0 0 95 95 10 1 
D 5827 B 10 9 1 2 24 26 8 2 
D 5828 A 7 7 5 458 25 483 aa 1 
D 5828 B 13 12 6 298 527 825 9 4 
D 5829 A 12 11 1 6 130 136 10 2 
D 5829 B 0 0 0 0 0 0 0 0 
D 5830 A 5 5 5 28 20 48 4 il 
D 5830 B 2 1 2 17 2 19 2 0 
D 5831 2 8 4 20 39 59 7 2 
D 5832 8 7 0 0 69 69 7 al 
D 5833 15 12 4 259 93 352 alal 4 
D 5834 8 tf 2 2 80 82 6 2 
D 5835 6 6 1 2 35 37 5 1 
D 5836 6 6 0 0 158 158 4 2 
D 5837 0 0 0 0 0 0 0 0 
D 5838 0 0 0 0 0 0 0 0 
D 5839 8 8 0 0 197 197 6 2 
D 5840 5 5 3 24 72 96 3 2 
D 5841 11 10 0 0 127 127 9 2 
Average number per haul, 1.85 45.59 134.8 180.3 4.83 1.06 
