30 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. tj. 



BECOBD OF COLLEOTIONB 



Larus argentatus. 



1927, August 13. 2, lengths 1.40 and 1.70 mm. 



L. atricUla. 



1913, August 15. 1, length 1.30 mm. (Cat. No. 7949, U.S.N.M.) 



ALARIA species 

 Figures 66, 67 



A single, somewhat damaged specimen from the intestine of a ring- 

 billed gull {Larus delawaren^is) , January 24, 1914, is here noted. 



The oral sucker and pharynx are missing, and the specimen is 

 broken at the level of the anterior border of the accessory adhesive 

 organ. 



Dimensions, balsam: Length 2.17 mm.; anterior division, length 

 1.40, breadth 0.42; posterior division, length 0.77, breadth 0.42: 

 diameter of ventral sucker 0.06; adhesive organ, length 0.17, breadth 

 0.10. The bursa is everted, length 0.14, breadth 0.22; cirrus exsertedy 

 length 0.14, diameter 0.05. 



Ova have not yet made their appearance. The anatomy is not satis- 

 factorily shown in the mounted specimen. Vitellaria extend from 

 about the middle of the posterior division forward to the ventral 

 sucker, and mask the anterior testis and ovary. (Cat, No. 7950, 

 U.S.N.M.) 



This distome suggests Hemistoniutn gaviuni (Guberlet)." 



"^ STRIGEA BURSIGERA (Brandcs) 



Figures 68-72 



1890. Holostotnum hursigerum G. Brandes, Zool. Jahrb., vol. 5, p. 592, figs. 



15-18. 

 1909. Strigea hursigera (Brandes) Luhe, Parasitische Plattwurmer. I. Trema- 



todes, Brauer's Suswasserfauua Deuchlauds, Heft 17, p. 163. 



Larus jndibundus. 



Woods Hole. Mass., Lat'us argentatus^ L. atricilla, L. delawarensis, 

 intestine. 



Length from 6 to 9 mm. ; anterior division of the body more or less 

 pyriform, posterior division subcylindrical, enlarging slightly to the 

 posterior third, where the greatest diameter is attained in the vicinity 

 of the testes. The anterior end is usually reflected dorsally. There 

 are some variations from the above proportions, but they can usually 

 be accounted for by different conditions of contraction. Oral sucker. 

 pharynx, and ventral sucker all small, the ventral a little larger than 

 the oral. The two testes are lobed and situated behind the middle 



• Joum. Parasit., vol. 9, pp. 9-11, figs. 10-13. 



