684 MR. F. E. BEDDARD ON NEW [DcC. 20, 



an opening into the gut. This arrangement, however, occurs in 

 Lumbricus, where it was first, I believe, accurately described by 

 Messrs. Marshall and Hurst in their ' Practical Zoology ' ; but it 

 has not been described in any other genera, and most certainly does 

 not exist in many Earthworms, e.g. Pontoscolex (=Urochceta), 

 where each gland opens by its own duct into the oesophagus. The 

 calciferous gland of the xvth segment has a rather smaller develop- 

 ment of the internal folds ; the duct leading to the oesophagus is 

 ciliated. The intestine begins in the xviiith segment. 



Another feature of interest in this genus concerns the male efferent 

 apparatus, which differs in detail from that of many other Earth- 

 worms ; the male pores are upon segment xvii. within the ventral 

 pair of setse ; each aperture is really double, though this point is not 

 recognizable without having recourse to section-cutting. The two 

 apertures of each side are enclosed by the swollen epidermis, of which 

 the cells are very elongated and at the same time narrow ; one 

 aperture lies in front of the other; the anterior of the two is 

 connected with the atrium, and through it project a few penial setse 

 which are enclosed in a muscular sac ; these penial setse have the 

 form illustrated in Plate XLVI. fig. 13. The atrium is not in any way 

 remarkable ; it belongs to the tubular type and is divided, as in 

 Acanthodrilus, &c., into a granular and a muscular portion. The vas 

 deferens near to its external opening, in fact from segment xv. 

 onwards, is enveloped by a thick muscular coat which is fully as 

 thick as is that of the atrium. I have already described in Pyg- 

 mceodrilus a similar muscular investment of the terminal region of 

 the sperm-duct ; and I have met with the same thing in two species 

 of Benhamia described above. 



The nephridia of this worm are diffuse. The position of the 

 male pores distinguishes the genus from Digaster, in which the male 

 pores are upon segment xviii. On the other hand, it is quite possible 

 that it is congeneric with Dichogaster as extended by Michaelsen to 

 include his new species B. minus and D. hupferi. The particular 

 points referred to in the above description are not mentioned by 

 Michaelsen ; accordingly it is uncertain how far I am justified in 

 creating a new genus. 



III. Genus Perionyx. 



This genus was founded by Perrier ^ for a worm closely related to 

 Perichceta, hvii differing from that genus by " the development of 

 the clitellum, the arrangement of the male orifices, the position of 

 the spermatothecse, and finally the clearness of the segmental 

 organs." Although the investigations of Perichceta which have 

 been carried out since Perrier's paper was published have led to a 

 necessary alteration of the wording of the above quoted phrase, there 

 is every reason to agree with Perrier in holding the genus Perionyx 

 as distinct from Perichceta. There is at present no reason for 



^ " Eecherches pour servir a I'histoire des Lombriciens, &c,," Nouv. Arch, 

 du Museum, t. viii. p. 126. 



