PLATE A. 



ANATOMY. 

 The Alimentary Canal and the Brain. 



Fig. 1. The alimentary canal and mandibles of Herieia 

 Robini, $ , seen from the side, X 190. 



2. The alimentary canal of Glycyphagus plalygaster, 



? , seen from the side, x 100. The anus is 

 seen through the wall of the rectum, and a 

 portion of the ventral cuticle surrounding it 

 is shown. A muscular band runs from the 

 cuticle to the rectum, also lines of connective 

 tissue. 



3. The alimentary canal of Tyroglyphns longior 



seen from the side. Reichert, Obj. 5, Oc. 1, 

 copied from Nalepa's figure (/), pharynx, 

 etc. (Schlundapparat). 



4. The alimentary canal of Tyroglyphus siro seen 



from above (no amplification given). Copied 

 from G-udden's figure. 



5. Sagittal section of the pharynx and surrounding 



parts of Glycyphagus platygaster, ? , X 350. 

 The mandibles rest on the anterior portion 

 of the roof (r r) in front of the perpendicular 

 bend. 



6. Salivary glands from one side of Glycyphagus 



platygaster, ? , X 350. 



7. Salivary gland of Tyroglyphus siro, copied 



from Gmdden's figure (no amplification 

 given) . 



8. Horizontal section through the brain of 



Herieia Robini, X 500, showing the starting 

 of the nerves to the legs and the genital or 

 splanchnic nerve. The section of the oesopha- 

 gus is shown in the centre of this and the 

 two following figures. 



9. Transverse section through the brain of Herieia 



Robini, <$ , cut about the middle of the supra- 

 cesophageal ganglion, X 500. 



