||P.2015 right column 2nd paragraph: "Chromosome organization: At first sight, the genome looks remarkably uniform, GC content (36%) is essentially unchanged across all the chromosomes, unlike the GC content in vertebrate genomes, such as human, or yeast (ref 45). There are no localized centromeres as found in most other metazoa. Instead, the extensive, highly repetitive sequences that are characteristic of centromeres in other organisms may be represented by some of the many tandem repeats found scattered among the genes, particularly on the chromosome arms. Gene density is also fairly constant across the chromosomes, although some differences are apparent, particularly between the centers of the autosomes, the autosome arms, and the X chromosome (Table 2 and Fig. 3)."