106 PROCEEDINGS OF THE NATIONAL, MUSEUM vol.88 



was seen. The uterus occupies the space between the shell gland and 

 the ventral sucker. The vitelline glands are marginal and extend 

 from a point a short distance back of the ventral sucker to a point 

 about halfway between the second testis and the posterior end. Meas- 

 urements of one of larger specimens in balsam: Length, 6.50 mm.; 

 maximum diameter, 0.75 mm. ; oral sucker, length, 0.67 mm., breadth, 

 0.60 mm.; pharynx, length, 0.28 mm., breadth, 0.21 mm.; ventral 

 sucker, length, 0.36 mm., vertical diameter, 0.24 mm. An average of 

 36 of the larger ova, in a series of sections, was 0.042 by 0.025 mm. ; 

 the largest observed measured 0.054 by 0.033 mm. 



From small-mouthed black bass : Collected by J. L. Robertson at 

 Culver Lake, N. J., one specimen in June, 1905, seven specimens on 

 November 15, 1907 (U.S.N.M. No. 8303). These distomes from the 

 black bass differ from those found in the piclierel in the relative posi- 

 tions of testes and ovary. In the distomes from the pickerel the 

 testes are separated from each other by a space equal to or greater 

 than the diameter of a testis, and the ovary is separated from the 

 first testis by a space about equal to its diameter, while in the dis- 

 tomes from the bass th(> testes and ovary are very close together, in 

 most cases being actually in contact with, each other. In four of the 

 six mounted specimens the ovary lies directly in front of the first 

 testis, in the others it lies beside the first testis, being crowded back 

 by the uterus. In an immature specimen 2.17 mm. in length the 

 ovary is separated from the first testis by a space nearly equal to its 

 diameter. In another, immature, specimen, 2.10 mm. in length, the 

 testes are in contact with each other, and the ovary is in contact with 

 the anterior edge of the first testis. An average of 15 of the larger 

 ova, in balsam mounts, was 0.056 by 0.029 mm. ; the largest, 0.057 by 

 0.030 mm. ; the smallest, 0.048 by 0.027. 



From cutlassfish: This record is based on a series of sagittal sec- 

 tions of one distome, and a series of frontal sections of the anterior 

 end of another. These sections occur in a lot which was prepared of 

 the distome Sterrhurus inonticellii from the cutlassfish. These sec- 

 tions are on a slide along with sections of a specimen of S. monii- 

 cellii. Careful search was made for other examples of Azygim 

 among the large number of S. inonticellii in the collection but none 

 were found. 



The agreement between this material from the cutlassfish and that 

 from the bass and pickerel is close. The testes and ovary are in con- 

 tact with each other, as in the bass. The vitellaria are lateral, be- 

 tween the lateral margin and the intestinal rami, distributed more 

 ventrally than dorsally, and extend from about 0.15 mm. back of the 

 ventral sucker nearly to the posterior end. Ova numerous, maximum 

 about 0.06 by 0.03 mm. Ova in the anterior folds of the uterus con- 

 tain miracidia. 



