T^NIA MEDIOCANELLATA. 133 



quickly as possible from those who suffer from this worm, so as to 

 cut off this possible constant source of the production of Cysticerci 

 in one individual. 



The Cysticerci in the subcutaneous cellular tissue and in the 

 anterior and posterior chambers of the eye which are within reach 

 of the knife, or the couching needle may be removed by cutting, 

 or broken up by the couching needles ; but this last process is 

 less advisable, as the chitinous structure of the vesicle does not 

 disappear by absorption. When the Cysticerci are in the vitreous 

 humour, we must, according to Von Graefe, endeavour to remove 

 them by incision of the sclerotica. 



With the Cysticerci living on the retina and in the brain, our 

 endeavours must, ex theoria, be directed to causing their death as 

 soon as possible, after which, as observation shows, fatty 

 degeneration, calcification, and shrivelling take place in the worm, 

 which may be accompanied by an alleviation of the symptoms in 

 consequence of a partial diminution of pressure, just as we see 

 this takes place after apoplexy. Unfortunately, however, we have 

 no means of effecting this object, and even in the eye, into 

 which, according to Donders and Graefe, certain remedies applied 

 externally can penetrate by absorption, experiments by dropping 

 in filicate of potash and preparations of santoiu were of no use, 

 according to Graefe. We must, therefore, wait quietly until the 

 parasite is destroyed by the favorable action of the organism, or 

 by time. How long a cystic worm may live in an organism, how 

 many years it may wait, without suffering injury itself or becoming 

 destroyed, or be converted into a Taenia when it gets into a 

 suitable intestine, are points unknown to us. If we knew these 

 things it would be possible to predict at what time the death of 

 the worm might take place, or a remission of the disorder be 

 expected. In short, there is no active treatment for the latter 

 purpose, although, according to Von Graefe, with those which are 

 seated beneath the retina, it might perhaps be possible to under- 

 take the operation by the employment of the speculum. 



2. Taenia mediocanellata (mihi). PI. Ill, figs. 11 — 13. 



Up to the time of Bremser a second species of Tienia made its 

 appearance from time to time in the system ; it was probably 

 known to Pallas, Brera, and Andry. Since Bremser's time, 



