EFFECTS OF BLADDER-WORMS IN THE EYE. 551 



the process one observes a blunt, proboscis-like projection. 1 In the 

 interior of this the quadrangular head may be recognised, which is 

 usually soon extruded, so that the whole appendage, with narrow 

 neck and wrinkled body, is free down to the constricted base. Gene- 

 rally the movement of the rostellum and suckers is to be seen ; they 

 are protruded in varying fashion, the head rotates on the neck, and 

 the whole appendage exhibits a periodic retraction, so that it some- 

 times approaches the bladder, and at other times projects directly 

 from it. At certain times the movements are almost continuous, 

 while at other times the appendage hangs out almost immoveably 

 from the bladder, so that one might readily suppose the worm to be 

 dead. 2 The movements of the worm are usually excited by the 

 contraction of the iris; by the use of atropine there is a marked 

 diminution, but whether by direct or indirect operation is uncertain. 

 The diamond-like glitter which one sometimes sees when the rostellum 

 is protruded depends probably on the hooks, which change their 

 position somewhat in consequence of the movement. Similarly, the 

 point-like excrescences on the bladder can hardly be anything but 

 the above -described microscopic projections characteristic of the 

 Cysticercus cellulosce. 



As in the aqueous, so it is in the vitreous humour, only of course 

 with this difference, that the movements are more and more restricted 

 by the threads and membranous thickenings which gradually develop. 

 In many cases a sort of capsule is formed round the worm. 



In the first edition of this work I have already expressed the 

 supposition, 3 which has been reiterated by my old friend v. Zehender, 

 that the bladder-worms of the chambers of the eye and of the vitreous 

 humour were not developed there, but were first embedded in the adja- 

 cent membranes iris or choroid and that they subsequently became 

 free, just as I have proved in regard to the bladder- worms of the body- 

 cavity (C. pisiformis and C. tenuicollis), which, after their passage from 

 the liver, remain fur a while free before they are ultimately sur- 

 rounded by a cyst. 



On closer scrutiny of the ophthalmological literature on this 

 point, and especially of the account which v. Wecker and Leber have 

 given in the well-known text-book on general ophthalmology by v. 



1 See von Wecker in " Handbuch d. ges. Augenheilk.," by von Graefe and Samisch, 

 Bd. iv., p. 708. 



2 See the observations of Sommering (loc. cit. ), and of Mackenzie, Med. - Chirurg. 

 Trans., vol. xxxii., 1849. 



3 Kiichenmeister expresses the same supposition in the second edition of his work on 

 parasites (p. 250), and imagines that he renders his own opinions of greater weight by calling 

 mine " an anatomical presentiment." 



