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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. maldivense. 



