252 Transactions of the Society. 



final shape. The envelope consists of a comparatively thick 

 exterior shell in which is a delicate sac thickened at the ends, 

 loose in the envelope, and containing the sporozoites embedded in 

 granular cytoplasm. 



The sporocysts remain in the vesicles during the life of the 

 worm, when they may reach the soil or may be eaten with the 

 host by a bird, but nothing is accurately known as to the subsequent 

 history. 



Seminal vesicles were dissected out in normal salt solution, 

 fixed in picro-formol (Bouin), cut in paraffin at 4 jx, stained in iron- 

 alum-h?ematoxylin, Heidenhain, and mounted in Gilson's euparal. 



An adaptation of Apathy's chloroform embedding method was 

 used to minimize shrinkage, in which the transference from chloro- 

 form to paraffin was very gradual, while the staining bath was 

 prolonged to 7-14 days. It was then found possible to differentiate 

 as usual in iron-alum, leaving the cyst walls nearly colourless, 

 while the contents were darkly stained. 



