544 THE ANIMAL PARASITES OF MAN 



and cachexia are absent. The simultaneous presence of the parasite in other 

 organs facilitates the diagnosis. 



Echinococci of the scrotum, the epididymis and the tunica vaginalis have 

 been observed in a few cases. 



Echinococcus of the bones is rare. In the Pomeranian statistics not a 

 single case is mentioned. 



The parasite is found more frequently in the long bones than in the 

 short bones. In the cases collected by Poppe, the frequency with which differ- . 

 ent bones were affected was as follows : Humerus 23 per cent., pelvis and tibia 

 18 per cent., vertebral column and femur 13 per cent., frontal bone 5 per cent., 

 sphenoidal bone, scapula, index finger, sternum, and ribs each 1 case. 



The parasite develops in the medullary cavity, i. e., in the spongy sub- 

 stance, and is at first entirely latent. Only with increasing growth do char- 

 acteristic changes occur. In the long tubular bones the medullary cavity 

 dilates, the wall of the bones becomes eroded, the external wall thin. Often 

 there is severe pain. Slight trauma leads to spontaneous fracture without 

 any previous symptom of disease of the bone. The fracture does not heal, a 

 fact which usually enables us to recognize the nature of the affection. Schnitz- 

 ler's case proves that occasionally, even in echinococcus of the long tubular 

 bones, decided changes in form and circumference of the bones may take 

 place. 



NEMATODA, THREAD-WORMS 



The nematoda are slender, cylindrical, curved, thread-like or tubular 

 worms. Their surface is smooth and curled, occasionally supplied with hook- 

 lets, hairs, or bristlets. The anterior end of the body in which the mouth 

 cavity is situated is somewhat slender, the posterior end is pointed or roimded. 

 The anus is usually found upon the ventral surface. The nematoda, at least 

 those which are parasitic in man, are of different sexes. The males, as a 

 rule, are shorter and more slender than the females. In the males the posterior 

 end of the trunk is usually curved, while in the female it shows a straight 

 elongation. In the male the sexual opening and the anus are one, while 

 in the female the former is usually found at about the center of the body. 

 Of the nematoda which are parasitic in man I shall briefly mention : 



Ehabditis terricola?, Dujardin, 1845, which was once found in the cadaver. 



Ehabditis pellio, Schneider, 1866, was found in acid urine containing albu- 

 min, blood and pus. I believe that I once saw this parasite with Westphal. 



Ehabditis Niellyi, Blanchard, 1885, in a cabin boy produced an itching 

 skin eruption. 



Anguillula putrefaciens, Kiilm, 1879, was once observed in vomitus. The 

 parasite was evidently taken into the stomach of the affected individual with 

 onions, and then had produced vomiting. 



Of decidedly greater interest is : 



Anguillula intestinalis et stercoralis, Bavay, 1877. 

 In 1876 ISTormand, a French marine surgeon, found, in the feces of a 

 soldier who suffered from the so-called Cochin-China diarrhea, anguillula which 



