TREMATODES FROM FISHES LINTON 81 



0.17 mm,; pharynx, length, 0.12 mm., breadth, 0.11 mm.; ventral 

 sucker, length, 0.18 mm., breadth, 0.22 mm. ; ova, 0.045 by 0.024 mm. 



From common pipefish: Ten, collected July 29, 1913; three fish 

 examined; collected by Dr. G. A. MacCallum. One (U.S.N.M. No. 

 8260), collected June 13, 1914. Measurements in balsam: Length, 

 2.10 mm., breadth, 0.38 mm. ; diameter oral sucker, 0.13 mm., of ven- 

 tral sucker, 0.25 mm. ; pharynx, length, 0.13 mm., breadth, 0.10 mm. ; 

 ova, 0.054 by 0.027 mm. Posterior end bluntly rounded ; the seminal 

 vesicle extends nearly half-way from ventral sucker to ovary. 



From puffer : Bull. U. S. Fish Comm. for 1899, p. 46*4, 1901. One, 

 collected August 16, 1906. Length in balsam, 1.4 mm. ; breadth, 0.49 

 mm. Three small distomes (U.S.N.M. No. 8261), collected August 

 21, 1918, from a 20 mm. fish. Length, life, 0.70 mm. (Fig. 20) . Meas- 

 urements in balsam: Length, 0.52 mm.; breadth, 0.31 mm.; oral 

 sucker, length, 0.08 mm., breadth, 0.11 mm.; pharynx, length, 0.09 

 mm., breadth, 0.09 mm. ; ventral sucker, length, 0.17 mm., breadth, 0.18 

 mm. ; ova, 0.042 by 0.021 mm. Resemble small distomes from mack- 

 erel ; elliptical, strongly contracted ; anatomy much obscured by vitel- 

 laria, which extend from posterior end to middle of ventral sucker; 

 muscular genital pore at left of pharynx. These distomes resemble 

 Distomum sp., from Opsanus tau (Bull. U. S. Fish Comm. for 1899, 

 p. 469, fig. 328,1901). 



From southern porgy: Bull. U. S. Fish Comm. for 1899, p. 458, 

 figs. 333, 334, 1901. One, collected August 1, 1904. One, collected 

 August 22, 1910. Ventral sucker prominent, with characteristic 

 undulate or papillate border; genital sucker seen distinctly, with 

 metraterm opening in front of it. 



From tautog: One, collected August 12, 1904; under slight pres- 

 sure, length, 1 mm. ; breadth, 0.45 mm. ; after killing over flame, under 

 pressure, length, 1.54 mm., breadth, 0.41 mm. 



A few, collected August 15, 1908 ; three mounted in balsam. These 

 taper to a blunt point posteriorly. Measurements, lateral view: 

 Length, 1.26 mm., breadth, 0.20 mm.; diameter of oral sucker, 0.10 

 mm. ; pharynx, length, 0.08 mm., breadth, 0.05 mm. ; ventral sucker, 

 length, 0.16 mm., breadth, 0.15 mm.; ova, 0.051 by 0.030 mm. Nine, 

 collected July 5, 1910; variety of shapes. It was noted that two of 

 these distomes differed from the others in having subtriangular testes, 

 the juxtaposed edges of which were diagonal instead of horizontal. 

 The posttesticular region of one was short and bluntly rounded, the 

 other tapered to a blunt point. Length of one, 1.26 mm.; breadth, 

 0.49 mm.; the other, length, 1.05 mm., breadth, 0.31 mm. The others 

 in this lot measured from 1.12 to 2.66 mm. in length. Two, collected 

 August 2, 1911 ; before flattening one of these was elongated and fili- 



155599—40 6 



