. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 42 bulletin: museum of comparative zoology. beginning at the third myotome and extending almost to the posterior end, a series of smaller spots in groups irregularly twice as numerous as the myotomes. The gonads form two series, one righfand one left, though, as intimated by Giinther (1889, p. 44), they are often so closely pressed together near the median phme that they there seem to form a single median row. The presence of a double row of gonads places tliis species untpiestionably in the genus Branchiostoma. The n
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 42 bulletin: museum of comparative zoology. beginning at the third myotome and extending almost to the posterior end, a series of smaller spots in groups irregularly twice as numerous as the myotomes. The gonads form two series, one righfand one left, though, as intimated by Giinther (1889, p. 44), they are often so closely pressed together near the median phme that they there seem to form a single median row. The presence of a double row of gonads places tliis species untpiestionably in the genus Branchiostoma. The number of gonads on each side Avas thirty-three, and the series ranged from the first to about the twenty-ninth myotome instead of the twenty-sixth, as in the " Challenger" specimen. Our specimen is probably a male, though the gonads were not sufficiently mature to allow this determination to be made with certainty. I can confirm the statement of most previous writers that oral cirri are absent. I have also been unable to find any evidence of branchial apparatus, and I agree with Cooper (1903, p. 353) that if this apparatus is present at all, it must be very limited in extent. Possibly the small size and flattened form of this species, which must place very near the surface all the living substance in need of oxygen, may have been acquired in connection with a gradual loss of special- ized respiratory organs in much the same way that many of our smaller sala- manders seem to have lost their lungs. Heteropleuron maldivense Cooper. Cooper, 1903, p. 349. Twelve specimens of this recently described species were dredged in sixteen fathoms of water at Hanimadu, Tiladummati Atoll. They agreed in all par- ticulars with the very full account of this species given by Cooper. The more important structural relations as shown in three of the specimens are given in Table I. TABLE 1. Structural Characteristics, etc., of H. Please note that these images are extracted from
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