DESCRIPTIONS OF GENERA AND SPECIES 531 



to have assumed an error of two segments; but it will be noted that in the figure illustrating 

 the anatomy of the species (3, PI. ii, fig. 17) the organs in question are placed in exactly the 

 same segments as they occupy in the description. The huge size of the species prevents me from 

 identifying it with any known species of Acanthodrilus, and, on the whole, I think it safer to leave 

 it in the category of a 'species inquirenda.' 



(2) A. veriicillatus. This worm is placed by Peeeiee in the genus Acanthodrilus, with a little 

 doubt, as the sexual apparatus in the individual which he studied was reduced to the four sacs of 

 penial setae. The length of the specimen was 350 mm. The setae are paired. The penial setae 

 are upon the seventeenth and eighteenth segments. There is a gizzard. Attached to each sac of 

 penial setae is a gland. I think that, from Pereiee's description, there is no doubt that the worm 

 is a member of the genus Kynotus, but, as this identification cannot be regarded as certain, I leave 

 it, for the present, among the Acanthodrilidae 'incertae sedis.' 



The above two species are the only two species named 'Acanthodrilus' about whose position in 

 the system there is great doubt; I think that RosA has correctly referred Einbeeg's Mandane 

 stagnalis to his species A. spegazzinii, which will be considered later (see below). 



(i) Acanthodrilus dissimilis, Beddaed. 



A. dissimilis, Beddaed, P. Z. S., 1885, p. 813. 



A, negleetus, Beddaed, P. Roy. Soc, Ed. xiv, p. 156. 



Deflnltion. Length, 143 mm.; breadth (at clitellum), 4-5 mm.; number of segments, 225. 

 Clitellum, XIV— XIX ; segments, XVII-XIX, with a ventral non-glandular area. Male 

 pores connected by a straight longitudinal groove. Prostomium completely divides buccal 

 segment. Setae paired. Dorsal pores visible in posterior region of body only. Gizzard 

 in VI ; calciferous glands in XV, XVI ; in XIV oesopliagus somewhat more globular 

 than in preceding segments, but this dilatation is not comparable in size to the calciferous 

 glands of XV, XVI. Intestine begins in XX. As the oesophagus gradually widens out 

 to form intestine, it is difficult to state precisely where the latter begins. The third to 

 the eighth septa after the gizzard are thickened. Hab. — New Zealand'^. 

 The remaining characters agree with those of A. parkeri. The spermathecae are 

 of the same form, but I never observed more than two diverticula to each. 



The diflferences between this species and A. parkeri are evidently but slight. 

 The main diflference is really one of size. The position of the gizzard, however, 

 seems to distinguish the two species, as also the greater number of thickened septa 

 in A. parkeri. On further consideration I reunite with the present species A. negleetus 

 which I formerly separated. The diflferences between the twp forms are limited, so 

 far as I was able to ascertain, to a difference in the position of certain papillae in 

 the anterior region of the body. At most, as it now appears to me, this diflference 

 is of value in establishing a variety. Benham has united the two species. 



' For notes on colour, locality, &c., of this and other New Zealand species, see W. W. Smith (2). 



3 Y2 



