20 PROCEEDINGS OF THE NATIONAL MUSEUM vol.75 



nates abruptly just posterior to acetabulum and extends to posterior 

 tip of body. Testes numerous, disposed in two rows commencing 

 about 490/i caudad of acetabulum and terminating about one-fourth 

 of bod}' length from posterior end. 



Female unlcnown. 



Cercaria unknown or unrecognized. 



Hosts. — Primary, birds {Hydrocoloeus nielanocephalus) ; second- 

 ary, unknown. 



Location. — Heart. 



Distribution. — Europe (Italy) . 



So far as may be determined from Parona and Ariola's (1896) 

 description, there appears to be no essential difference, as Odhner 

 (1912) points out, between Or^nithohilharsia howaJeioskii and O. can- 

 aliculata. The available descriptions are, however, so incomplete 

 that a study of specimens of these species is necessary before final 

 decision should be made. 



ORNITHOBILHARZIA ODHNERI Faust, 1924 

 Figures 43-45 



Specific diagnosis. — OrmthohiJharzia : 



Mide 6 to 7 mm. long by 220/x to 260yu, in cross section. Cuticle 

 covered with spines. Oral sucker 120ju, to 155/-t in diameter; aceta- 

 bulum 160|a to 165jti in diameter. The gynaecophoric canal is deep 

 and broad. The esophagus branches immediately cephalad of the 

 acetabulum; intestinal ceca sinuous, uniting caudally six-sevenths of 

 body length from anterior end; common cecum short. Testes oval, 

 about 65 in number, and lying in median line in equatorial three- 

 sevenths of body. Seminal vesicle situated midway between anterior 

 testis and acetabulum, and communicating directly with a rudimen- 

 tary cirrus pouch which lies' dorsad of the genital pore; ejaculatory 

 duct rudimentary ; prostate absent. 



Female 3 mm. long by lOOju, to 120/x in diameter in cross section. 

 Cuticle covered with fine spines. Oral sucker and acetabulum equal 

 in size and measuring TO,a in diameter. The esophagus bifurcates 

 cephalad of acetabulum, and the intestinal ceca unite about four- 

 fifths of body length f i*om anterior end ; common cecum short. Ovary 

 elongate, loosely coiled, and situated in anterior third of body. The 

 oviduct arises from the posterior pole of ovary, bending laterad and 

 continuing anteriad to the ootype ; seminal receptacle well developed, 

 situated behind the ovary, and connected with oviduct by a short duct. 

 Laurer's canal arises from dorsal aspect of seminal receptacle and 

 opens through a minute pore on dorsal side of body. The vitellaria 

 consist of paired follicles extending from a short distance caudad of 

 seminal receptacle to near posterior end of body. The vitelline duct 



