156 Transactions of the Societtj. 



them our present species most nearly resembles. To take the 

 most important organs first : — 



Two pairs of spermathecoe are found in the majority of species, 

 opening in the intersegments 7/8, 8/9. One pair only occurs in 

 K. macdonoldi Eisen. Copulation papillie exist in K. papillifera 

 Eosa, K. stagnalis (Kimb.), and some others. A small or rudi- 

 mentary gizzard (Muskelmagen) is found in A', garmani Kosa, 

 K. saltensis Bedd., A", rosx Bedd., K. macdonaldi Eisen, and 

 K. eiseniana Rosa ; it exists in K. kilkenthali Mich., and is well 

 developed in K. asunscionis Rosa, K. haloj^hild Bedd., A! suhandina, 

 while none is found in A", stagnalis (Kimb.), A", impillifera Rosa, 

 and K. rubra Friend. But A", stagnalis and K. papillifera have 

 muscular papillae on segments 17 and 19 where the prostates open, 

 whereas tliese are usually wanting in other species, including 

 rubra. 



Emphasis is laid by some systematists on the position of the 

 external pore of the spermathecse. If we name the seta3 Irom the 

 ventral to the dorsal a, b, c, d, then the spermathecse may be said 

 to open in a line with a, b, c or d, or between any two of these. 

 Thus the spermatliecte of A'! subandina open midway between setiP c 

 and d, whereas in A', halophila (Beddard's type species) the opening 

 is in the line a b. In this respect A", rubra is unlike the foregoing, 

 but approaches A! macdonaldi and A", eiseniana, whose sperma- 

 theca? open immediately below c, but in each of these the sperma- 

 thecse differ from those of K. rubra. 



K. rubra, therefore, occupies a position of its own, and it is on this 

 account, perhaps unfortunate, that we have no means of knowing 

 its original home. It may be possible to assign a place to K. rubra 

 by following Michaelsen's classification. 



8 



I Prostate opening through muscular papillae 

 \ Opening of prostate simple 

 Girdle forming a complete ring . 

 Girdle saddle-shaped 

 Prostate doubled .... 

 Prostate single .... 



. j Spermathecal pores in line ah . 

 [ Spermathecal pores in line cd . 

 . \ Girdle ring-shaped, 14-19 segments . 

 \ Girdle weak ventrallv, lo-*20 segments 

 „ I Spermathecffi with outgrowths . 

 I Spermathecse bottle-shaped 



1. A', stagnalis 



2. K. papillifera 



3. K. zonalis 



2 

 3 



4 

 5 

 6 



4. K. halophila 



5. K. asu/iscio7iis 



6. A^ macdonaldi 



7. K. rubra 



In the three last species the girdle is on segments 13-20, and 

 the spermathecse of K. asunscionis resemble those of A", rubra. 

 But while in K. ruhra the gizzard is absolutely wanting, and in 

 K. macdonaldi at best rudimentary, in A', asunscionis it is fully 

 developed. 



