jiBT.i TREMAJODE PARASITES OP BIRDS — LINTON 29 



PROALARIA INDISTINCTA (Guberlet) 



Figures 64, 65 



•1922. Hemistomum confusum Gtjbeelet, Journ. Parasit., vol. 9, pp. 11-12, figs. 



4-9. 

 1923. Alaria inc^istincta (Gubei'let), Gtjberi.et, Trans. Amer. Mic. Soc, vol. 41, 



p. 68. 

 1926. Proalaria indistmcta (Guberlet), LaRub, Trans. Amer. Mic. Soc, vol. 45, 



p. 15. 



Larus delawarensis, intestine. 



Woods Hole, Mass. : Larus argentatus^ L. atricilla. 



The following description is based on the specimen from 

 L. atricilla. 



Dimensions, life: Length 1.30 mm.; anterior portion, length 0.60, 

 breadth, 0.60 ; posterior portion, length 0.70, diameter 0.40. 



Dimensions in balsam, compressed, and margins of anterior por- 

 tion folded : Length 1.22 mm. ; anterior portion, length 0.56, breadth 

 0.36; posterior portion, length 0.66, breadth 0.38; pharynx, length 

 0.045, breadth 0.036; oral sucker, length 0.054, breadth 0.051; ventral 

 sucker, length 0.058, breadth 0.075 ; diameter of adhesive organ 0.15 ; 

 ovum 0.092 by 0.061. 



Anterior portion of body broader and slightly shorter than pos- 

 terior portion; oral sucker and pharynx each longer than broad, 

 ventral sucker broader than long; pharynx adjacent to oral sucker; 

 accessory adhesive organ close to posterior border of ventral sucker. 

 Two conspicuous organs, one on either side of the oral sucker, 0.045 

 by 0.072 mm. in the two principal diameters, ha^e a rasplike appear- 

 ance under high magnification. Each is crossed by about 12 trans- 

 verse ridges. Upon focussing up and down, these structures appear 

 to be the roughened edges of a series of plates set on edge and close 

 together. 



The rami of the intestine originate very close to the pharynx and 

 extend to the posterior end of the body. The two testes lie on the left 

 side, the anterior one near the middle and the posterior one at about 

 the posterior third of the posterior division of the body. They are 

 separated by a fold of the uterus. The ovary lies on the left side at 

 the anterior border of the first testis. The vitellaria extend through- 

 out the entire length of the posterior division of the body, and as far 

 forward as the posterior border of the ventral sucker, and obscure the 

 other structures to a great degree. The ova are relatively large, not 

 numerous, and mainly on the right side, from the posterior edge of 

 the accessory adhesive organ to the posterior end. A few lie between 

 the testes. The dense vitelline glands make it difficult to see details 

 of the anatomy. The genital pore is dorsal, about 0.06 mm. from 

 the posterior end. 



