FIGURE 10a in Vulcanolepas scotiaensis sp. nov., a new deep-sea scalpelliform barnacle (Eolepadidae: Neolepadinae) from hydrothermal vents in the Scotia Sea, Antarctica

FIGURE 10a. Ratios of peduncle to capitulum length. The "gracile" form (shown as series 1, a diamond) is the less ornamented variety, and by far the most abundant in the collections. During growth, the peduncle can grow up to 20 times the length of the capitulum. The trend line included is for the "gracile" form only; the R2 correlation of this regression at 0.72518 confirms a reasonable correlation—i.e. that with growth, the pedun11 cle can be expected to become proportionately longer. However, the "robust" variety (shown here as series 2, a square) has subequal p:c ratios, and this apparently changes little with growth (= age), such that some larger specimens may even possess a capitulum that is slightly longer than the peduncle. This part of the graph is isolated and used in Figure 10b. Data base 57 specimens ("gracile" from JC42 F-0396 (34), JC42 F386 (10); "robust" 13 from JC42-F0122). p = peduncle length, c = capitulum length.