118 REPOET— 18G4. 



mixed with simple moist horse-dung, which Avas also examined (September 

 23), with the following result : — Many were found alive, one or two being 

 active, but most of them closely coiled upora themselves in various ways. 

 Those that were stretched out and apparently hfeless were afterwards seen 

 to move slowly their slightly curved tails. In one example the digestive 

 tube, from mouth to anus, seemed well developed and complete, and in none 

 of them did there appear to be any traces of decomposition. 



On the 5th of October, 1863, I re-examined the AnguiUules in the pear 

 and found them still aUve. The longest measured ^L-". 



On the 28th October, 1863, I commenced a new series of experiments 

 (ten in number), with the view of verifying the previous results. I again 

 procured a considerable number of perfectly fresh eggs, containing embryos, 

 and placed them in portions of decayed apples and pears ; and in aU cases I 

 examined these fruits with high magnifying powers, previous to my employ- 

 ing them for experiment. In no single instance could I detect the presence 

 of AnguiUulce, or any other kind of animal parasite, within their parenchyma. 



On the 30th December, 1863, T re-examined the apples and pears, which 

 had all become mouldy. In none could I find any free embryos ; and the 

 contents of the eggs appeared to have perished, the eggs themselves having 

 turned to a yellow-brown colour'. I strained off the pulp in water, for sub- 

 sequent examination, before finally abandoning this series of experiments. 



On the 4th Januaiy, 1864, I commenced another series of experiments, 

 with the view of again testing the results above mentioned. I procured two 

 partially decayed pears and one apple, and (having by careful microscopic 

 examination satisfied myself that they contained no animal parasites of any 

 kind) I inserted several entire female Oxyurides, and also a few loose ova, 

 into each. A very large proportion of the eggs contained the characteristic 

 tadpole-like embryos. On examiaing the decayed fruits, on the 20th April, 

 1864, I could find no trace of the embryonic Oxyurides ; neither were there 

 any AnguiUules. 



These several sets of experiments appeared sufficient to establish the fact 

 that we cannot rear the eggs of embryos of O.vyuris either in fresh or in de- 

 caying vegetable matters. 



The presence of AnguUlules in the original experiment must be regarded 

 ' as accidental ; but as their development is not without interest, I may, 

 before dismissing the subject, further observe that, on the 30th December, 

 1863, I reexamined one of the pears, which was first employed for experi- 

 ment more than a year previously (December 22nd, 1862). In the pulp 

 (which was perfectly free from mould, though stiU in a loosely closed vessel) 

 I found large numbers of Anguillides in every conceivable stage of develop- 

 ment, from the early free embryo, measuiing -^~', to the sexually mature 

 condition, measuring -^J'. Some of , them contained a single egg. There 

 were also a few discoloured Oxyurls-eggs, with dead granular contents, and a 

 considerable number of free AnguiUuline ova. These latter were pale, almost 

 colourless, and contained actively moving embryos in their interior, totally 

 unlike those of Oxyuris. On the 20th April, 1864, hundreds of the Anguil- 

 lules were stiU living. They were still living on the 21st of July last, and, 

 I have no doubt, are yet in the enjoyment of an active vitality. 



Eggs of Oxyuris, containing embryos, placed in water on the 22nd Decem- 

 ber, 1862, and others again on the 4th of January, 1864, failed either to 

 develope further or to set free their embryonic contents. 



On the 5th October, 1863, I placed some fuU-grown female Oxyurides in 

 pure fresh water. On examining the water (December 23, 1863), I found 



