BY JAS. P. HILL. 6 



The largest specimen found during my last collecting trip in 

 May was a sexuall}'' mature male, measuring, in the living condi- 

 tion and when only very moderately extended, about 12 cm. in 

 length with a breadth in the tail region of 7 '25 mm. In August 

 of last year, I found another large specimen which measured in 

 the contracted condition about 18 cm. In the fully extended 

 condition, this specimen, now in the teaching collection of the 

 Biological Department of 83Tlney University, reached a length of 

 over 25 cm. The majority of the animals were, however, very 

 much shorter and thinner. They are capaljle of very considerable 

 extension; for examj^le, one specimen w^hose tail region had a 

 transverse breadth of only 1*75 mm. reached in the fully extended 

 condition a length of 11*7 cm. 



Proboscis : The proboscis is relatively short like that of Ft. 

 iiiiniUa and Ft. sarniensis. It varies in shape and length during 

 life; when the animal is progressing it is more or less elongated, 

 and when at rest generally somewhat egg-shaped, the latter being 

 the shape it almost invariably takes when the animals are 

 preserved in chrom-osmic acid. The proboscis of the first large 

 specimen referred to above had a length of about 1 mm. in the 

 living condition. 



Collar: In the living animals the surface of the collar is smooth 

 and in them, as well as in preserved specimens, it can readily be 

 divided into the five characteristic regions (fig. 1). The first region 

 includes slightly more than the anterior half of the collar, and is 

 formed by the anterior free part of the latter. It spreads out 

 anteriorly, investing the neck and base of the proboscis like a 

 frill with margins crinkled as well during life as in preserved 

 specimens. Behind the frill-like anterior region the collar is 

 strongly contracted to form a well marked circular groove — the 

 second region [figs. 1 and 15 (2)] — the anterior margin of which 

 lies immediately above the mouth aperture. This groove is 

 slightly more marked on the ventral side than on the dorsal. 



The groove is followed by a prominent circular cushion of a 

 lighter colour forming the third region [figs. 1 and 15 (3)]. Behind 



