Australian Eartlnvorms. 253 



begins in 17. Special bunches of nephridia present in the 

 pharyngeal region. 



(b) Microscopic. — In the simple portion the lining is slightly- 

 folded, and has goblet cells scattered about among the columnar 

 epithelium. There are two definite muscular layers, and the 

 peritoneal layer is composed of granulated cells with large 

 nuclei. Of the vascular swellings, the most anterior have low 

 folds in the lining, which increase in length in the following 

 segments, until, in the most posterior swellings, the structure is 

 similar to the typical vascular swelling represented in Fig. 8. 



EXPLANATION OF PLATES XLVITI-Ll. 



Fig. 1. — Longitudinal vertical dissection showing typical posi- 

 tion of pharyngeal mass and crop. 

 2. — Transverse section of calciferous glands of Fletchero- 



drilus unicus in segment 14. 

 3. — Transverse section of calciferous glands of Cryptodrilus 



saccarius, showing the two diverticula separated 



from median canal by ducts. 

 4. — Transverse section of typical pharynx, through anterior 



portion of dorsal mass. 

 5. — Transverse section of typical pharynx through median 



portion of dorsal mass, showing small amount of 



glandular tissue. 

 6. — Transverse section of typical pharynx through posterior 



portion of dorsal mass, showing glandular mass. 

 7. — High power view showing typical structure of crop. 

 8. — Transverse section across a vascular swelling, with long 



folds of lining and large blood supply. 

 9. — Transverse section of oesophagus in segment 16 of 



M. dorsalis, showing ciliated lining. 

 10-16. — Dorsal views of alimentary canal- of M. dorsalis, M. 



fielderi, M. tenax, C. saccarius, F. unicus, D. haJceri 



and D. tanjilensis. 

 17. — Pair of calciferous glands of C. saccarius (median canal 



cut open). 

 18. — High power view of section showing structure of wall 



of calciferous gland of C. saccarius. 



