On two new Amphistome parasites of Sumatran fishes. 673 



the skin. The terminal round niouth is sometimes siirrounded by an 

 elevated margin. Sucker is at the margin of the tail end. It is 

 «ircular, but sometimes projects backward with a swollen margin. 

 An eminence behind the mouth carries the genital opening-. The 

 illustrations as far as they go, except for the lancet form and pointed 

 head and the irregularity and projection of the posterior sueker, 

 might well repi-esent the form under consideration. 



A. cyl i n d r i c u m. A. corpore cyUndrico, utrinqiie ohtnso, transversim 

 riujoso, ore terminali orhicidari promimdo; acetabtdi suctorii orbictdaris 

 lateralis limho elevato. Measures 4 lines (9 mm) by 2 lines (4,5 mm) 

 white, body cylindrical rounded at the ends, transversaly wrinkled, 

 mouth terminal, circular with elevated margin. Circular sucker 

 lies just anterior to the posterior and with a broad margin. The 

 illustration shows merely the outline. There is nothing in this 

 description with is inconsistent with that of our form, nor is there 

 anything which could insure their identity. 



On the whole, notwithstanding the close relation that must exist 

 between these forms, it seems best on account of its different host 

 and the sliglit differences which do exist, to give this worm a 

 specific name. Possibly if Diesing's material is still in existence a 

 detailed examination of his forms may make clear the relation. A 

 brief anatomical description for diaguosis may be given as follows: 



Cladorchis pangasi. 



Body elliptical, flattened with thick, rounded edges, measures 

 6—3,5X3,1—2 mm. Anterior or mouth sucker small, posterior sucker 

 round, not sinuous, embedded ventrally, just subterminal. Ovary 

 anterior to posterior sucker; Laurer's canal opens medially in front 

 of median excretory outlet; festes lobulated, situated anterior to 

 ovary one in front of the other; pharynx club-shaped, muscular; 

 small lateral buccal pouches: pigmented branches of excretory System, 

 probably connected with the network of tubules in the skin. 



Cladorchis helostomatis n. sp, 



The second bottle coutained two specimens of a small trematode, 

 one of which was cut into sagittal sections. after being compared 

 with the other. 



The Worms were found in the stomach of Helostoma temminchi 

 (K. et V. H.) which is a labjTinth fish also collected in Palembang, 



Sumatra. 



45* 



