AUT. 7 CESTODE PARASITES OF BIRDS LINTON 61 



Genus FIMBRIARIA Frblich s 



Examples of this genus have been collected by Mr. Edwards in 

 the Woods Hole region from Mergus serrator, Oidemia deglandi, 

 O. perspicillata, Fulica americana^ and Harelda hy emails. There is 

 great diversity of shape and form presented by the representatives 

 of this genus in the collection, but, so far as I am able to deter- 

 mine, after a study of manj'^ whole mounts and series of sections, 

 they are referable to two species only, namely, the widely dis- 

 tributed species Fimbriaria fasciolaris and the new species F. fal- 

 ciformis. 



FIMBRIARIA FASCIOLARIS (Pallas) 

 Figures 194-199 



Scolex. — Minute, at the extremity of a pennon-like pseudoscolex ; 

 rostellum with a circle of 10 hooks. The dimensions of the scolex 

 agree with those given in the literature of the species. Thus, in one 

 case, the breadth of the scolex was 0.10 mm.; breadth of sucker 

 0.036, length 0.045; diameter of circle of hooks 0.03; length of hooks 

 0.02. 



The pseudoscolex is reflected until it is nearly or quite at right 

 angles to the strobile. There is, moreover, a tendency to extend 

 laterally, in a more or less rounded projection, at the base. This 

 is best seen in young specimens. It is thus easy to distinguish this 

 species from F. falciformis^ which latter, especially in young speci- 

 mens, has a sickle-shaped pseudoscolex. The length of the pseudo- 

 scolex, to which the scolex, whose dimensions have been given above, 

 was attached, was 6 mm. ; its gi'eatest breadth 1.5. 



Strobile. — Unsegmented, although the closely crowded transverse 

 wrinkles give the appearance of segmentation. Genitalia, except in 

 a very rudimentary state, rather remote from the scolex; genital 

 pores unilateral, and very closely crowded together. In a series of 

 transverse sections not exceeding 0.015 mm. in thickness, portions of 

 as many as three cirrus-pouches may be seen in a single section. 

 The cirrus is short, and is armed with numerous, minute spines; 

 length of larger, basal spines about 0.006 mm. The cirrus-pouch is 

 nearly cylindrical, its length approximately four or five times the 

 diameter, as for instance, length 0.15; breadth 0.030; its inner por- 

 tion acts as a seminal vesicle. The vas deferens connects with an 

 inner seminal vesicle. There appear to be three testes, one situated 

 at a distance equal to about one-fourth the breadth of the strobile 

 from each lateral margin, and one near the median line ; vasa effer- 

 entia convey sperm from these to the inner seminal vesicle. 



^ For synonymny see Taenioid Cestodes of North American Birds. Ransom. Bull. 69, 

 U. S. National Museum. 



