CONTRIBUTIONS TO AMERICAN HELMINTHOLOGY. 57 



tion. It may be similar to the " Schluck-ceffniing " observed by 

 Vogt in certaia mariiie TrematodesJ 



The genital orifice, as in D. dimorphum, is situated behind the 

 ventral sucker about 1 mm. No cirrus was detected. The oval 

 eggs have a thickish yellow shell, with a lid at the narrow end, and 

 measure 0.099 mm. by 0.066 mm. 



2. — DiSTOMUM ASPERXJM, n. Sp. 



One of the two examples of Botaurus minor above referred to 

 yielded ten specimens of a Distome occupying two varicose dilata- 

 tions of the bile-duct, recalling the swollen bile-ducts described by 

 Cobbold* in a Porpoise. The worms proved to belong to Dujardin's 

 sub-genus Echinostoma; and I at first believed that they might be 

 D. ferox, Zeder, first detected by Goeze in dilated intestinal follicles 

 of Ardea stellaris. I was more inclined to do so from discrepancies 

 in the various descriptions of this form.^ Certain peculiarities, how- 

 ever, seem to me to mark it off from that species, of which it is 

 undoubtedly a near relative, and I accordingly propose the specific 

 name " asperum " for my specimens. 



Description (Figs. 3, 4, 5). — Body yellowish white, 8.19 mm. long, 

 1.8 mm. broad in middle, tapering gradually to each end; the head 

 and anterior part of neck narrower than tail ; covered entirely with 

 persistent spines 0.054 mm. long, somewhat sparse posteriorly ; liead 

 reniform, with a coronet of 27 obtusely-pointed spines, four of which 

 on each side of a median ventral notch are larger (0.155 — 0.16 mm.) 

 than the others (0.117 mm.), and radiate from nearly a common point 

 of origin; anterior sucker terminal, with projecting circular lip 0. 14 

 mim. in diam. ; ventral large (0. 75 mm. ), situated at junction of anterior 

 and middle thirds of body. ViteUigenous glands chiefly in neck, but 

 accompanying intestinal coeca to posterior end. 



The orbicular neck of D. ferox, its deciduous spines only present 

 anteriorly, the position of its ventral sucker, and the constriction of 

 the body there, together with the arrangement of the coronal S]3ines, 

 seem to distinguish it effectually from D. asperum. ^° The genital 



1 Zeit. f. Wiss. Zool., B. XXX., Suppl., p. 307, f. 



8 Jour. Linn. Soo. XIII., p. 39. 



9 For lit. see Dies. Syst I., p. 387; Molin. Denkschr. d. k. Akad in Wien XIX., p. 219; 

 Olsson, Kongl. Svensk. Vetensk. Akad. Handlingar. XIV., p. 22. I have not access to Van 

 Beneden's paper, "Sur la eicogne blanche et ses parasites." Bull. Acad. Belg. XXV. 



10 Cf. Fig. 4 with Olsson's Fig. 50 loc. cit. ; also V. Linstow's descr. Trosch. Archiv., 1873, 

 p, 106, and Dujardin's. 



