DIOCTOPHYMIM; 431 



everywhere, so that human beings may become infected by 

 unexamined trichinous pigs from their own country or from abroad,, 

 and also because an infection may occasionally escape notice. For 

 these reasons the meat imported into Berlin from abroad as free 

 from Trichinae is examined again and not always in vain ; finally, also, 

 gross negligence may at times occur, or fatal errors may be made. 



In addition private prophylaxis must not be neglected, and its 

 chief aim should be directed to the suitable preparation of pork. 



Family. Dioctophymidae. 



Genus. Dioctophyme, Collet-Megret, 1802. 



Syn. : Eustrongylus, Dies., 1851. 



Large worms. Anterior extremity unarmed ; the mouth is surrounded by six 

 papillae. One ovary. The vulva is in the anterior region of the body. 



Dioctophyme gigas, Rudolphi, 1802. 



Syn. : Dioctophyme renale, Goeze, 1782 ; Ascaris canis et martis, Schrank, 1788 ; 

 Ascaris visceralis et renalis, Gmelin, 1789 ; Strongylus gigas, Rud., 1802 ; Eustrongy- 

 lus gigas, Dies., 1851 ; Strongylus renalis, Moq. Tand., 1860 ; Eustrongylus visceralis \ 

 Raill., 1885. 



Colour blood-red ; the anterior extremity somewhat slender ; 

 there is a series of about 150 papillae along the lateral lines ; the 

 sub-median lines are strongly developed, and from them spring the 

 radial muscles for the intestine. 



The males attain a length of 40 cm. and a diameter of 4 to 

 6 mm. ; the posterior extremity is transversely truncated ; the anal 

 orifice is within the base of the collar-like bursa, the thickened edges 

 of which are beset with papillae ; the spicule measures 5 to 6 mm. 

 in length. 



The females attain a length of 100 cm. and a breadth of 12 mm. 

 The anus is crescent-shaped and terminal. The vulva is 50 to 

 70 mm. distant from the anterior extremity. The eggs are oval and 

 have a thick shell presenting numerous depressions ; the shell itself 

 is brownish, but it is colourless at the somewhat thickened poles ; 

 it measures 60 //, in length by 40 //, in breadth. The larva measures 

 240 IJL by i4/-t. 



Dioctophyme gigas lives in the pelvis of the kidney, more rarely in 

 the abdominal cavity of the seal, otter, dog, wolf, fox, horse, marten 

 and polecat, exceptionally also in human beings. It also occurs in 

 tumours of the mamma and perinaeum. Most of the cases in which 

 this parasite has been reported as occurring in man may be traced 

 back to unrecognized Ascaris lumbricoides or to clots of fibrin ; seven 

 certain cases, eight more or less doubtful, however, remain. 



