Earthworms of the Vienna Museum. 129 



upon a given segment are separated from each other bv wide 

 intervals. 



The setae upon the general body-surface are not orna- 

 mented, which is a further point of resemblance to Diachmta 

 Thomasii ; but tiicy were in a few cases unmistakably bifid, 

 as in Pontoscolex corethrurus. It is seldom that the free 

 extremity of the seta3 in either of these species shows the 

 bilidity clearly; they are generally apparently too much 

 worn, and a faintly marked notch, readily passed over, alone 

 indicates the cleft. It is quite possible, therefore, that Ponto- 

 scolex arenicola and Diachceta Thomasii may really possess 

 the same notched setie which Perrier first described and 

 figured for ^^Uroclueta corethruray The sette upon the 

 clitellar segments are larger than some of the others and are 

 distinctly ornamented with a series of crescentic ridges limited 

 to the distal part of the seta. This particular form of seta is 

 very characteristic of the Geoscolecidie, particularly upon the 

 clitellum, and the fact that similar setta occur in Griodrihis 

 is a strong argument for regarding that genus as being related 

 to this family. Benham makes no remark about the cli- 

 tellar setse of Diachctta Thomasii. I may mention that this 

 peculiar ornamentation of the setse in the Geoscolecidse often 

 requires some looking for ; it is not always very strongly 

 marked. 



As in the last species, there is no prostomiura. 



The clitellum is extensive, occupying segments xvi.-xxxi. 

 Schmardahas mentioned that the clitellum sometimes consists 

 of lilteen rings, commencing with the fifteenth. 



The nephridia are furnished with those peculiar cup-like 

 bodies at their termination which Perrier first described in 

 Fontoscolex corethrurus and regarded as sphincters for the 

 closure of the nephridial pore. 



The spermathecai (figs. 4, 5) are exceedingly long thin sacs, 

 hardly, if at all, dilated at the blind extremity, where the 

 semen is stored. There are here again only two pairs ; each 

 measures about 5 millim. in length, which is half the circum- 

 ference of the worm in the region where they occur. 



The mucous gland, gizzard, and thick mesenteries appear 

 to be as in the last species. 



^^Hypogceon orthostichon,^^ Schmarda, 



This species clearly belongs to the family Cryptodrilidse, 

 which comprises the majority of the Australian earthworms : 

 it is not a characteristic family in New Zealand — at present 



Ann. ii) Mag. N. Hist. Ser. 6. Vol. ix. D 



