code: private boolean matchesSpecies(final NamespaceHeader hdr, int species) {
          final String speciesHdr = hdr.getNamespaceBlock().getSpeciesString();
  
          // empty header, no match
          if (noLength(speciesHdr)) {
              return false;
          }
  
          // non-numeric, no match
          if (!isNumeric(speciesHdr)) {
              return false;
          }
  
          // convert and match
          int v = Integer.parseInt(speciesHdr);
          return v == species;
      }
docs: Match a {@link NamespaceHeader namespace header} to a species taxonomy
  id.
  
  @param hdr {@link NamespaceHeader}
  @param species {@code int} species
  @return {@code true} if the namespace data is specific to
  {@code species}, {@code false} otherwise