130 ANIMAL PARASITES. 



whether they lay in or behind the retina. In five months the 

 first vesicle was completely collapsed, and instead of it a folded, 

 transparent, membrane, without determinate outlines, was to be 

 seen waving up and down, and the second vesicle also was less 

 distinctly detected with indeterminate outlines. The animal, 

 however, was still alive, and its head lay towards the nose. 

 Cystic worms appeared on no other part of the body, nor did the 

 patient suffer from tape- worm. 



In a second case, in which no Cysticerci appeared on ether 

 parts of the body, but in which segments of Tceni<s were passed, 

 glimmerings, cloudy vision, and complete dimness of sight appear 

 to have established themselves gradually in the right eye, in 

 which inflammation had from time to time been set up, accom- 

 panied by violent attacks of headache on the right side, until at 

 last only a slight appearance of light remained. By means of the 

 speculum, a round, vesicular body, with the before-mentioned 

 undulatory movements, was seen above the place of entrance of 

 the optic nerve. Its fine, bluish-green colour was deadened by a 

 slight veil (enveloping membrane). As if inverted in the vesicle, 

 a white head was seen, which alternately extended and retracted 

 a neck. In this case also the above-mentioned greenish spots 

 were seen upon the retina. In course of time the shining colour 

 gradually disappeared ; but there was no change in the form and 

 size of the entozoon. In nine months instead of the vesicle, 

 only a colourless membrane, or a sj-stem of such membranes, 

 which covered the greater part of the hinder surface of the eye, 

 was seen floating in the vitreous humour. The sensibility to light 

 had entirely disappeared. Although, as already remarked, there 

 was no external appearance of Cysticerci, Graefe thinks that the 

 previous weakness of one arm, the violent headaches, the 

 glimmering, and the subjective appearance of light in the other 

 eye, must be referred to a simultaneous existence of Cysticerci 

 in the brain. 



In a third case, Graefe saw the vesicle shining immovably to 

 the right in the outer part of the back of the eye, through a 

 septum of translucent membranes, which penetrated the hinder 

 part of the vitreous body ; he saw the movements of the vesicle 

 and the neck distinctly, but the sucking discs indistinctly. This 

 eye was quite blind ; the other was healthy. There was no trace 

 of a tape-worm, or of Cysticerci, in other parts of the body. 



In the latter cases, at the first glance, the greenish colour, 



