APPENDIX B 171 



8. Eyes 9 pairs; oral sucker bears small papillae; from 

 Southern Ocean 9 



— Eyes 0-3 pairs; oral sucker generally without papillae 10 



9. Body with narrow trachelosome and broad flattened 

 abdomen Trulliohdella 



— Body not clearly divided into regions . . . . Cryohdellina 



10. Mouth at about the centre of oral sucker 11 



— Mouth in anterior border of oral sucker 30 



11. Posterior sucker small, little or no wider than the 

 posterior end of the body 12 



— Posterior sucker considerably wider than the posterior 

 end of the body 15 



12. With a row of at least 8 pulsatile vesicles on each side 



of abdomen 16 



— Pulsatile vesicles absent or no more than three on each 

 side 13 



13. Anterior sucker relatively huge, nearly as wide as the 

 short flattened abdomen Ganymedehdella 



— Both suckers very small 14 



14. No eyes Hemibdella 



— Eyes 1 pair on about tenth annulus; suckers almost 

 covered by annuli Myzohdelld 



15. With a row of pulsatile vesicles on each side 16 



— Pulsatile vesicles absent or indistinguishable . . . . 18 



16. With about 8 pulsatile vesicles on each side . . Cyrillohdella 



— With 11-13 pulsatile vesicles on each side 17 



17. Abdomen broad, somewhat flattened and very distinct 

 from narrow trachelosome; suckers rather small, 

 narrower than abdomen Trachelohdella 



— Abdomen more or less rounded and not very dis- 

 tinct from trachelosome; posterior sucker wider than 

 body Calliobdella* 



♦The New Zealand genus Makarahdella, Richardson 1959 (Trans, roy. 

 Soc. N.Z. 87,283) resembles Calliobdella in having 3 (6) annuli per somite 

 but differs in that the bursa lacks an accessory muscular organ. Possession 

 of 7 (14) annuli per somite in a leech of this kind would indicate a marine 

 species of Piscicola or Cystobranchus. 



