I9lt;] Michael, ct al. : Hijdrographic Records of Scripps Institution 217 



B. TABULATION OF DATA 



1. GENERAL EXPLANATION OF TABLES 



a. Armiigenicnt. — For convenience in tabulation and reference, 

 the data are presented in three tables. The hydrographie data, becavise 

 of their intrinsic value, are tabulated first. Therefore the data relative 

 to all temperature and salinity observations made since 1912 in the 

 ocean and in San Diego Bay are tabulated in tables 1 and 2 respec- 

 tively. F'inally. the field data relative to all plankton collected since 

 1912 for quantitative investigation are tabulated in table 3. All three 

 tables are arranged on the same general plan. 



b. Recording of position. — All positions are entered in latitude and 

 longitude measured from Greenwich. "Whenever the position is known 

 to have varied by more than one quarter mile during a single collect- 

 ing period, the latitude and longitude relative to each water sample 

 and net haul are not entered as such : instead, the initial and final 



position together with thi.s statement are given: "From to 



the boat drifted (or steamed) from the above to the follow- 

 ing position." the blanks being filled in with the times corresponding 

 to the two positions. In all other ca.ses the position corresponding to 

 each observation is entered. 



c. Meaning and use of sections. — For readily specifying the ap- 

 proximate position of observations, the region explored has been 

 divided into rectangular sections whose east and west boundaries are 

 five minutes in latitude, and whose north and south boundaries are 

 five minutes in longitude. The exact position of the center of each 

 section is specified by either a number giving its distance (in units of 

 5') west, or a negative number giving its distance east, of 114° W, and 

 either a subscript giving its distance nortli or an exponent giving its 

 distance south of 32° N. The two base lines, 32° N and 114° W, were 

 chosen entirely with reference to explorations, past and future, of the 

 Scripps Institution, the former in order to avoid the need of large 

 subscripts, and the latter in order to exclude large numbers and avoid 

 the need of referring to observations east of the selected meridian. 

 We did not contemplate making observations south of Cerros Island, 

 which lies in the fourteenth section west of 114° W, but, during the 

 winter of 1914, opportunity was unexpectedly oft'ered for taking a few 



