Benham. — Tu-0 Neiv Sj^ecies of Leech in N.Z. 



189 



land specimens agree with one another and in pattern, which 

 differs from that of H. australis. It may be suggested that here 

 we have two well-marked " local varieties " of one and the 

 same species. Possibly this is the case ; but if we turn to 

 measurements we find that H. australis is a broader leech, and 

 has a larger sucker. 



The contrast with the present species is perhaps best 

 rendered evident by a comparison of the two following dia- 

 grams : — 



I 



die d e f 



ab c ii e f 



Explanation of Text Figures A and B. 



Colour pattern of (A) Hirudo mauiatia and (B) H. australis "(copied from 

 Schmarda). In both the various bands are lettered — in A, a is 

 olive-green ; h, greenish-yellow ; c, c, olive-brown ; d, bright-yellow ; 

 /, reddish-orange : in B, a, c, e are very dark olive (nearly black) ; 

 b, c, yellow ; /, brownish-orange. 



Grube gives the measurements of two individuals (presum- 

 ably preserved), and Schmarda gives the dimensions of another 

 (apparently living). Taking a medium-sized individual (Grube's) 

 and comparing it with a specimen from New Zealand of corre- 

 sponding length, we have, — 



Length. 

 Mm. 

 .. 72 



H. australis 

 H. mauiana 



70 



Of internal structure we know nothing, excepting the jaws, 

 of which Schmarda says that each jaw bears forty-eight to fifty 

 denticles ; and he shows them arranged along the entire margin, 

 to increase in size towards one end, and to be of much greater 

 size than in H. mauiana. 



If Grube's synonymy be correct, I believe I am justified in 

 creating a new species. 



Hirudo antipodum, Benham. 



My previous article (2) dealt only with such external features 

 as seemed to be diagnostic of the species. I have now to give 

 a brief account of the internal organs, as seen on dissection 

 of a small specimen 25 mm. in length. The alimentary tract 

 agrees in the main with H. medicinalis, though I was able to 



