86 ^Ir. W. Xlcoll on iJie 



ornlrcs of llie two suckers) lias also a fairly constant pro- 

 portion. It >vas "S-'i-'JO mm., representing a ])roportion of 

 ^— jl of the body (uitlioiit ajipendix). The oral snekcr has a 

 diameter of "ll-lO mm. and the ventral 'IS-'^l mm. The 

 relative ; roju^rtion may therefore be approximately 1 : 2 or 

 2 : 3, not invariably 2 : 3 as Liihe has it. The pharynx is 

 contiguous with the oral sucker and has a length of OO mm. 

 with a breadth of '06-07 mm. The oesophagus is very 

 short or absent. The intestinal diverticula may extend into 

 the appeudix, but usually do not. The cuticle of the body 

 is ringed ('' geringelt ")^ that of the appendix is deeply 

 striated. 



The genital aperture lies a short distance behind the 

 ventral lip of the oral sucker ; the genital sinus is long and 

 extends almost as far back as the ventral sucker. The pars 

 prostatica is also of great length ; the prostate cells are very 

 numerous and form a dense mass behind the ventral sucker. 

 In consequence of the length of the prostate, the vesicula 

 seminalis is at a great distance behind the ventral sucker. 

 Tlie distance as measured is from '6 mm. to "9 mm., i. e. 

 rather more than | of the body-length. The seminal vesicle 

 is doul)le and usually lies towards the left side. The testes are 

 just behind it and one is almost directly behind the other, 

 the obliquity being very slight. They are globular or some- 

 what ovoid and of fair size (diam. "I^-'IG mm.). The ovary 

 and vitelline glands lie almost midway between the testes 

 and the beginning of the appendix. The ovary is always 

 elliptical, the long axis being transverse, and measures 

 •13-'18 X •11-12 mm. It is thus about the same size as the 

 testes. The yolk-glands lie close behind and ventral to the 

 ovary, and arc each about the same size as the ovary ; they 

 are slightly lobed. one usually having three, the other four 

 lobes. This coincides, curiously enough, with Lube's 

 observations in the eases where the yolk-glands are tubular. 

 The glands are at a distance of '4-"6 mm. from the ai)pendix. 

 The uterus is very voluminous and may extend a siiort dis- 

 tance into the appendix, but usually does not. The ova are 

 numerous and measure •022-"028 mm. X 011-012 mm. 



Hemiurus communis, Odhner. 



From the oesophagus, stomaf;h, and intestine of Ammodyies 

 tobiunus and from the stomach of Gadus (Bylejinxis. 



This si)ecies .-hows very great resemblance both to 

 //. appendiciduius and to H. Luhei. It is dift'ert ntiated from 

 the former by the situation of the testes, which are close 



