376 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



GENERIC DIAGNOSIS OF PARVACREADIUM 



Allocreadiinae of small size, with smooth skin. Acetabulum with a 

 single large anterior and a similar posterior lobe. Posterior end broad and 

 truncated, usually bilobed, or of very irregular contour. Prepharynx with 

 internal thickening. Genital pore near pharynx. Seminal vesicle coiled, 

 not reaching posterior to acetabulum. Genital sinus very short. Cirrus sac 

 rudimentary. Cirrus weak. Seminal receptacle lacking. Type species: 

 Parvacreadium bifidum. 



The generic name is from parva (= small) and creadium and indi- 

 cates a small, creadium-like trematode. The specific name bifidum indi- 

 cates the bifid posterior end. 



Discussion. Because the cirrus sac of this trematode is so inconspicu- 

 ous, the genus might be thought related to the Anallocreadiinae. Actual- 

 ly, it differs from that subfamily in lacking body spines and a seminal re- 

 ceptacle as well as in the presence of a delicate but definite cirrus sac. Par- 

 vacreadium is probably most closely related to Cymbephallus Linton, 

 1934. Cymbephallus also has a very weak and small cirrus sac, a smooth 

 cuticula, and, like Parvacreadium, a uterine seminal receptacle. Further- 

 more, certain Cymbephallus species possess acetabular processes. Parva- 

 creadium differs from Cymbephallus in shape of the body, small size, the 

 large acetabular lobes, the far anterior seminal vesicle, and reduced cirrus. 



Bianium adplicatum, new species 

 (Plate39,figs. 56, 57) 



Hosts and Localities: 



Cheilichthys annulatus (Jenyns) from Albemarle and 

 Charles islands, Galapagos, and San Francisco, Ecuador 

 Spheroides angusticeps (Jenyns) from Charles Island, 

 Galapagos 



Location : Intestine 



Number: One to several in 5 hosts 



SPECIFIC DIAGNOSIS OF BIANIUM ADPLICATUM 



Length 1.58 to 2.43; greatest width 0.73 to 1.08; anterior half of 

 body flattened with inrolled edges making it scoop shaped ; ventrolateral 

 folds extending a short distance posterior to acetabulum where they may 

 turn medianly but do not unite ; posterior half of body more or less cylin- 

 drical ; body spined anteriorly, spines disappearing on hindbody ; both ends 

 of body broadly rounded, anterior end subtruncate. Oral sucker circular 



