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structure observed by liim or Delia Cliiaje in Taenia ocellaia, 

 and Dujardin (Histoire naturelle des Helminthes, Paris, 1845) 

 has observed exactly the same structure of the uterus in a tape- 

 worm of the European Picas major. 



As in other tapeworms, the spermatozoa were very fine, fili- 

 form, of one diameter throughout, without the so-called head or 

 body of other spermatozoa. But what was very strange, these 

 spermatozoa were of very different lengths; some twice, thrice, 

 or even four times as long as others. Moreover, they would 

 readily break into pieces, and were not so soft and pliable as 

 they generally are. I saw several break into two pieces, (par- 

 ticularly when coming out from the cirrus-bag,) and both pieces 

 moved on. Whether this phenomenon occurred accidentally, or 

 whether it was a natural characteristic of these spermatozoa, I 

 am at a loss to say. No water was used in the examination, of the 

 bad effects of which upon spermatozoa I am fully aware. In either 

 case this is a subject worthy the investigation of physiologists ; 

 for such a power of division would imply a nature in these sper- 

 matozoa entirely different from what we have hitherto observed. 

 Other spermatozoa present individual elements ; on the contrary, 

 those of this tapeworm would be really dividual, at least virtually, 

 as they have the faculty of dividing and thus multiplying them- 

 selves. Not the slightest difference could be observed, in activ- 

 ity, movement, or form, between the divided portions and the 

 whole animals ; so that we may suppose, that each of the divided 

 pieces had the fructifying power, as well as the others. Further- 

 more, the motion of these spei-raatozoa was extraordinary. 

 Whilst others move in a peculiar, quick, vibratory manner, these 

 progi-Css much more slowly, in a succession of long curves, 

 reminding one of the motion of an eel at the bottom of a 

 river. 



This same tapeworm is also remarkable for the strange shape 

 of its eggs. While the eggs of tapeworms generally are globular 

 or oval, the shape of these was that of a large ball running out 

 on both sides into tubes which terminated in balls, of about half 

 the diameter of the central one. I found these eggs in all stages 

 of development, some containing nothing but a clear yolk, while 

 others presented embryos with six little spines. The yolk as 

 well as the embryo was found only in the central ball, and there 



