FLEMINGER and HULSEMANN: FOUR SIBLING SPECIES OF PONTELLINA 



Figure la. — Geographical distribution of sampling stations. Each open circle represents one or more samples. Over- 

 lapping stations and replicate sampling are omitted for the purpose of clarity. Areas intensively surveyed are shown 

 symbolically as evenly spaced grid. 



40° N 



20° N 

 0° 

 20° S 



— '40°S 



92° W 



Figure lb. — Distribution and identification of sets of quantitative zooplankton samples used to estimate the frequency 

 of Poniellina in the Pacific Ocean. Sets were selected for similarity of sampling; i.e., each set obtained by the same 

 procedures and stations occupied in a closely ordered sequence during the same cruise. Dots indicate the sampling 

 localities. Indian Ocean localities represent Indian Ocean Standard Net samples collected during the International 

 Indian Ocean Expedition that were examined quantitatively for Pontellina in the course of this study. See Table 14 for 

 summary of sampling data and Materials and Methods for analytical details. 



65 



