1920] 



Allen: Plankton of the San Joaquin River 



213 



Table 2. — Organisms Per Cubic Meter in Plankton of 

 San Joaquin River in 1913 — [Continued) 



1913 



8/ 2 



8/ 9 



8/15 



8/23 



8/31 



9/ 6 



9/13 



9/20 



9/27 



10/ 4 



lO/U 



10/18 



10/26 



11/ 1 



11/ 8 



11/15 



11/22 



11/30 



12/ 6 



12/14 



12/20 



12/27 



Trachelomonaa 

 volvocina 



158,688 



264,480 



423,168 



317,376 



740,544 



317,376 



423,168 



528,960 



423,168 



317,376 



211,584 



158,688 



211,584 



105,792 



158,688 



52,896 



79,344 



1,600 



52,896 



l,t00 



Volvox 

 aureus 



12,800 

 6,400 



" ejioo 



12,800 



Total 

 Mastigophora 



2,696,000 

 3.029,366 

 2;035,748 

 3,644,928 

 3,622,528 

 4,664,256 

 5,491,600 

 3,436,544 

 4,902,032 

 7,761,216 

 5,959,952 

 8,780,736 

 8,581,952 

 4,157,280 

 3,438,240 

 4,281,184 

 7,096,616 

 4,446,464 

 5,277,552 

 2,996,624 

 2,310,576 

 796,640 



Amoeba 

 proteus 



3,200 

 528,960 



"211^584 



3,200 



Amoeba 

 radiosa 



211,584 



105,792 



12^800 

 52396 



"l58,688 



1,600 



Arcella 

 vulgaris 



1913 



1/ 5 



1/12 

 1/19 

 1/25 

 2/ 2 

 2/ 8 

 2/15 

 2/23 

 3/ 1 

 3/ 8 

 3/15 

 3/23 

 3/29 

 4/ 5 

 4/13 

 4/19 

 4/26 

 5/ 3 

 5/10 

 5/17 

 5/24 

 5/31 

 6/ 7 

 6/li 

 I /21 

 6/28 

 7/ 5 

 7/12 

 7/19 

 7/26 

 8/ 2 

 8/ 9 

 8/15 

 8/23 

 8/31 



Cyphoderia 

 ampulla 



DiflBugia 

 corona 



52,896 



12,800 



3,200 



6,400 



"12,800 



Difflugia 

 pyriformis 



400 

 1,600 

 1,600 

 12,S00 

 19,200 

 3,200 

 9,600 



6,400 

 6,400 



79,344 

 32,000 



19,200 

 6,400 

 634,752 

 793,440 

 158,688 

 211,584 

 185,136 

 158,688 

 132,240 



"l2,800 

 6,400 



"19,200 



105,792 



Hyalodiscus 

 sp. 



Microgroiiiia 

 socialis 



79,344 



3,200 

 3i7,37'6 



1,600 



158,688 

 158,688 



105,792 

 158,688 

 211,584 



Total 

 Rhizopoda 



400 



1,600 



1,600 



12,800 



98,544 



4,800 



12,800 



1,600 

 3,200 



16,000 



8,000 



132,240 



88,096 



22,400 



6,400 



634,752 



104,944 



158,688 



211,584 



189,936 



158,688 



146,640 



3,200 



171,488 



168,288 



3,200 



131,392 



1,189,312 



647,552 



