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6. Notes on Worms. 



By Dr. J. Stafford, Montreal, Can. 



eingeg. 14. März 1902. 



1) Aspidogaster conchicola von Baer occurs in the pericardial 

 cavity and kidney of Unio dilatatus taken from the St. Lawrence River 

 at Point St. Charles, Montreal. /,-.'•,;■■.- 



2) Distomtim sp., encysted in the transparent body-wall along 

 the margin below and up the sides in front of the pericardial region. 

 When set free they measure about 1,5 mm in length but when fixed 

 and mounted 1,2 mm by 5 mm. Mouthsucker 0,171 X 0,179 mm. Ven- 

 tral sucker 0,207 X 0,220 mm. There is a large pharynx and the lateral 

 caeca of the intestine extend to the posterior end. Immature, but rudi- 

 ments of genital organs can be made out: ovary and shell-gland right 

 and left close behind ventral sucker; testes larger than these, one be- 

 hind the other a little farther back ; vitellaria above and outwards from 

 the caeca from the ventral sucker to the posterior end; genital open- 

 ing in front of ventral sucker. 



3) Distomum pelafjicum^ described in Zoolog. Jahrbb., Aug. 1900, 

 I now believe to be a young Hemiurus [Apoblema). Adult worms be- 

 longing to this group occur abundantly in Clupea, Osmerus, Gadus, 

 Melanogrammus, Pollachius, Salmo, Sebastes, Anguilla, Hippoglossus, 

 Pleuronectes, Platysomatichthys, Cryptacanthodes, Hemitriplerus, and 

 Acanthocottus. 



4) Distomum [Spatì ndium) folium von Olfers, from the urinary 

 bladder of a Cat Fish (Amiurus nebulosus), differs in some respects 

 from the European form. 



5) Distomum [Bunodera] nodulosum Zeder, from the intestine of 

 the Brook Trout (Salvelinus fontinalis), also differs from the European 

 form. 



6) Distomum isoporum [Creadium isoporum) Looss, from the Chub 

 (Semotilus bullaris Raf ), is perhaps also distinct from the European 

 worm. 



7) Diplo&tomum sp., encysted round the pharynx of the Chub. 



8) Distomum {Br achy coelium) hospitale^ Zool. Jahrbb., Aug. 1900, 

 is the American representative of D. crassicolle Rud. It occurs in 

 Plethodon as well as Dierayctylus. 



9) Distomum [Cephalogonimus] sp., from the duodenum of Rana 

 virescens and R. clamitans, with genital opening in the middle line 

 above the mouth sucker. Habitat, size, external appearance, skin, 

 resemble D. quietiim (Zool. Jahrbb., Aug. 1900), but caeca shorter, 



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