1889.] OLIGOCHiErOUS fauna of new ZEALAND. 3/9 



Dorsal blood-vessel completely double. 



Alimentary tract. Tlie gizzard occupies segments vi. & vii. 

 Calciferous glands appear as a dilatation of the walls of the oesopha- 

 gus in segments xiv. & xv. 



Intersegmental septa dividing segments vii.-xii. specially thickened. 



Seminal sacs in segments ix., x., xi., xii. ; those of the last two 

 segments are racemose in appearance. 



Nephridia diffuse, with numerous external pores. 



Spermatheca furnished with a variable number of small diver- 

 ticula. 



6. ACANTHODRILUS ROS^, U. Sp. 



Prostomium completely dividing the buccal segment. 



Seta strictly paired, the pairs, at least in the posterior region of the 

 body, being equidistant. 



Clitellum extending over segments xiv.-xix. 



Dorsal pores present in the posterior segments of body. 



Dorsal blood-vessel double, but the two tubes unite at the point 

 where they perforate the septa. 



Intersegmental septa not specially thickened in the anterior 

 segments. 



Nephridia one pair to each segment, alternating in position, some- 

 times opening by dorsal, sometimes by ventral pair of setae. 



SpermatheccE with a long muscular diverticulum, bearing at its 

 extremity a cluster of small pouches. 



Genus Deinodrilxjs, F. E. B. 



Deinodrilus, F. E. Beddard, Quart. Journ. Micr. Sci. vol. xxix. 

 p. 105. 



Earthworms with 12 setse in each segment, arranged at approxi- 

 mately equidistant intervals. Prostomium not completely dividing 

 buccal lobe. Clitellum occupies 3 segments (xiv.-xvi.) as in Perichceta. 

 Nephridia diffuse, opening on to exterior by numerous pores in each 

 segment. Reproductive organs as in Acanthodrilus, i. e. two pairs of 

 tubular atria opening on to segments xvii. and xix. Vasa deferentia 

 open on segment xviii. Dorsal blood-vessel completely doable. 



7. Deinodrilus benhami, F, E. B. 



Deinodrilus benhami, F. E. Beddard, Quart. Journ. Micr. Sci. 

 vol. xxix. p. 105. 



Genus PerichjETa, Schmarda. 



PerichcBta, Schmarda, Neue wirbellose Thiere, Bd. ii. p. 13. 



Megascolex, Horst, Notes from Leyd. Mus. vol. v. p. 182. 



Perichceta, Perrier, Nouv. Arch. Mus. t. viii. p. 96. 



As the arrangement of the species of this very large genus is under- 

 going revision, I abstain from attempting a generic definition. The 

 species described below perhaps merits generic separation, as it differs 

 from most other species in such important points as the possession of 

 tubular atria and paired nephridia. 



