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PROCEEDINGS OF THE NATIONAL. MUSEUM 



number on any date was 6, from 42 fishes on one occasion, from 23 

 on another. On seven dates but one distome was recorded; on one 

 of these dates 50 fishes were examined. 



Five (U.S.N.M. No. 8240), collected September 16, 1912; 10 fishes 

 examined. 



Table 2'^.— Measurements of four specimens of Homalometron pallidum 



in balsam 



Measurement 



Length 



Maximum breadth 



Oral sucker, length 



Oral sucker, breadth 



Length of prepharynx 



Pharynx, length 



Pharynx, breadth 



Length of esophagus 



Ventral sucker, length 



Ventral sucker, breadth 



Ova (collapsed) 0.096 by 0.051. 



Mm. 

 1.54 

 .45 

 .IS 

 .19 

 .07 

 .10 

 .10 

 .00 

 .20 

 .19 



From kingfish: Three (U.S.N.M. No. 8291), collected September 

 11, 1907. Measurements, life, compressed : Length, 4.5 mm. ; breadth, 

 anterior, 0.36 mm., middle, 0.32 mm., behind testes, 0.78 mm.; oral 

 sucker, length, 0.26 mm,, breadth, 0.25 mm.; pharynx, length, 0.14 

 mm., breadth, 0.08 mm.; ventral sucker, length, 0.26 mm., breadth, 

 0.26 mm. ; ova, 0.10 by 0.06 mm. Prepharynx longer than pharynx ; 

 esophagus short. The seminal vesicle at its anterior end dorsal to 

 the posterior edge of the ventral sucker, extending back to ovary; 

 seminal receptacle somewhat elongated, at right side of seminal 

 vesicle, and extending back dorsal to ovary. 



Five (U.S.N.M. No. 8292), collected October 24, 1912; two fishes, 

 length, 150 mm., examined. 



Eight, collected October 31, 1912; ten fishes, length 125 nrni., ex- 

 amined. Length, 1.98 mm. ; breadth, 0.5 mm., in formalin. Most of 

 these distomes, mounted in balsam, are strongly contracted. In one 

 the vitellaria were reduced so that the intestines could be seen. They 

 reached to within 0.18 mm. of the posterior end. 



Forty (U.S.N.M. No. 8293), collected August 28, 1928; 34 fishes, 

 81 mm. to 137 mm. in length, examined. 



These distomes, in balsam, vary from 1.3 to nearly 5 mm. in length, 

 and are of great variety of shapes and proportions, as shown in the 

 followino; table: 



