364 



PLATE XI 



Fig. 1. Small portion of a very thin longitudinal section through the cuticle, 

 and one of the hooks occurring in it, of Distomum hepaticum L. /, the 

 hook, a, the dark, pellicle-like border of the cuticle ; beneath this a 

 layer, &, corresponding to an alveolar layer. Then follows the very dis- 

 tinctly alveolar outer stratum, c, of the cuticle, passing internally into 

 the fibrous portion, d, which contains numerous granules. Below the 

 cuticle are cross - sections of the circular muscle fibres, e, which are 

 embedded in a fibrous alveolar protoplasm. Picro -sulphuric acid, iron- 

 haematoxylin, water. Obj. 2 mm. 1'40, Oc. 18. Cam. luc. x 3275. 



