674 BULLETIN 82, UNITED STATES NATIONAL MUSEUM. 



MTZOSTOMUM, 8P. 



Occurrence. Free-living. 

 Host. Glyptometra tuberosa. 



Locality. Challenger Station 210, off Panglao and Siquijor, Philippines, 375 

 fathoms. 



MTZOSTOMUM, SP. 



Occurrence. Free-living. 



Host. Amphimetra molleri or Zygometra comata. 



Locality. Padau Bay, Mergui Archipelago. 



MTZOSTOMUM, 8P. 



Occurrence. Free-living. 



Host. Possibly TJiaumatometra tennis; Professor von Graff gives the host as 

 " a small form of Antedon." 

 Locality. Vladivostock. 



MTZOSTOMUM, SP. 



Occurrence. Free-living. 



Host. "Antedon, sp." 



Locality. Blake Station 219, off St. Lucia, 151 fathoms. 



PROTOMTZOSTOMA POLTNEPHRIS FEDOTOV. 



Occurrence. Endoparasitic, in the genital organs. 



Hosts. Two ophiurans of the family Gorgonocephalidse, Gorgonocephalus 

 eucnemi-s (Miiller and Troschel) and G. arcticus Leach. 



Localities. Kola Fjord, 100 to 180 meters (in Gorgonocephalus eucnemis) ; 

 Kara Sea (in G. arcticus). 



STELECHOPUS HTOCIUNI VON GRAFF. 



Occurrence. Free-living. 



Host. Hyocrinus bethellianus (in the original description given as Hyocrinus 

 bethellianus and Ilycrinus australis, but later corrected). 



Localities. Challenger Stations 146, west of the Crozet Islands (lat. 46 46' S., 

 long. 45 31' E.), 1,375 fathoms; and 147, between Marion Island and the Crozets 

 (lat. 46 16' S., long. 48 27' E.), 1,600 fathoms. 



Dr. L. E. Griffin reports finding undetermined species of myzostomes on speci- 

 mens of Stephanometra echinus and S. oxyacantha taken at Port Galera, Mindoro, 

 Philippines. 



It is an interesting fact that the myzostomes are parasitized by several internal 

 organisms belonging to groups not known to infest their hosts. 



Nansen has described a tapeworm, Tcpnm myzostoma, from Myzostomum 

 graffi. Dr. Brayton H. Ransom writes me that from Nansen's description it is 



