ECTOPAKASITIC TREMATODES. Zöö 



proceeding slightly backwards but mostly towards the left side 

 to the level of the hind end of the ovary, where it turns for- 

 wards and becomes the ootyp. Vitellaria extending from near 

 the front end of the intestine to near the hind end of the body 

 proper. Paired yolk-ducts arising in the middle of the body 

 proper and uniting in the median line at the front end of the 

 ootyp ; the single yolk-duct opening into the oviduct at a short 

 distance from the ootyp. Vaginal opening dorsal and median ; 

 vaginal canal long and dividing into two just before opening 

 into the paired yolk-ducts. Testes small and about 55 in number, 

 extending posteriorly to a short distance in front of the hind 

 end of the vitellaria. 



Habitat. — Gills of weak-fish {Cyiioscion regale). 



Loc. — Newport, K. I. 



Acanthocotyle Vei'rilli n. sp. 

 (PI. XXI, figs. 25 & 26.) 



The genus Acanthocotyle was founded by Monticelli in 1888 

 ['88, p. 97], and two species were subsequently described by him 

 ['90, p. 2-3].* 



* While the present paper was awaiting for tlie press I received the first number of the 

 " Archives de Parasitologie, t. ii," in which is contained a paper by my friend, Prof. F. S. 

 Monticelli, on the present genus ['99]. In it the author describes a new species, the third of 

 the genus, named A. oUgoterus. That tlie species here described can not be identified with the 

 above named one is, however, beyond doubt, as may be seen from a comparison of the follow- 

 ing text with the description of Monticelli. 



There is another point on which I wish to make a remark, viz. the position of the 

 genital openings. The plates to accompany Monticelli's paper is unfortunately not yet published, 

 but it appears from his descriptions that in all the European species the male and vaginal 

 pores lie in the median line, and the female pore on tlie left side close to the lateral mar- 

 gin. As stated in the text, my observations were made on a single mounted specimen, and 

 although I believe them to be in the main correct, still examination of serial sections is in 

 all similar cases exceedingly desirable. I must therefore leave my statements to be confirmed 

 or rectified by somebody having sufficient material. 



