FLEMINGER: INTEGUMENTAL ORGANS IN GENUS EVCALA^US 



scoring of individual perforations as represent- 

 ing particular sites contains an element of 

 judgment on the part of the observer. 



Constant repetition of pattern (per body 

 segment per species) in the distribution of 

 perforations (see Figures 9, 11, 13, 15) and the 

 small amount of variation in the total number 

 of perforations observed in each species (Table 

 4) indicate that personal judgment by an ex- 

 perienced observer introduces negligible bias. 

 The range about the mean number of perfora- 

 tions per species (Table 4) does not exceed 10% 

 with exception of si(bte)U(ii<, a special case 

 actually representing three allopatric popula- 

 tions occupying separate regions of the world's 

 tropical belt. Indeed, perusal of Table 4 indi- 

 cates that quantitative variation is not a simple 

 function of either sample size or total number 

 of perforations. 



With respect to presenting variation scored 

 for each species, the frequency of a perforation 

 appearing at each designated site is presented 

 symbolically in three categories: sites occupied 

 in all specimens, sites represented in 80 to 99% 

 of the specimens, and sites represented in 10 to 

 79% of the specimens (see Figures 9, 11, 13, 15). 



Table 4. — Number of localities, size of pooled sample, and 

 number of observed perforations in species of Eiicakiiuis. 



1500 r 



1000 



1-9 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99 100 

 OCCURENCE (%) OF PERFORATIONS AT DESIGNATED SITES IN Eucolanus 



Figure 4. — Frequency of occurrence of perforations at 

 designated sites on the dorsal and right lateral integument 

 of Eucalanus. The frequencies found in each species are 

 grouped in class intervals of 10*^ and each class is summed 

 for all species. Each designated site represents the occur- 

 rence of a particular type of integumental organ appear- 

 mg in a KOH-treated specimen as a distinctive perforation 

 in the integument and occupying a topographically 

 unique place within the framework of the overall bilateral- 

 ly symmetrical pattern found in the species. For purposes 

 of this graph the appearance of such a distinctively placed 

 perforation in only one specimen of the pooled sample for 

 the species is sufficient to include it among the number of 

 designated sites found in the species. Graph based on 

 examination of 448 adult female specimens representing 

 17 species that yielded a total of 1,709 designated sites as 

 defined above. 



Sites found in less than 10% of the sample have 

 been omitted. A general summary of the vari- 

 ability at each site is presented in Figure 4. 

 Roughly 80% of the sites were represented by a 

 perforation in every specimen. In 10% of the 

 sites a perforation was observed in 80 to 99% 

 of the sample. The remaining 10% of the sites 

 were occupied at lower frequencies, but this 

 category includes a number of sites that show 

 remarkable patterns of geographical variation 

 in subtenuis that are discussed below. 



Designated sites do not vary with respect to 

 type of organ they represent, but one class of 

 variation in topographic relationship is note- 

 worthy. As mentioned above, peg sensilla 

 regularly occur adjacent to the pore of an inte- 

 gumental gland. The peg and pore pairing often 

 varied with respect to the position of the two 

 relative to the orientation of the segment. The 

 peg tends to be lateral to the pore, but this may 

 be completely reversed or appear at any inter- 

 mediate stage about a 360° arc. As a pair, how- 



979 



