252 DESCRIPTIONS OF EARTHWORMS. 



Oil Acanthodrilus Schlegelii Horst and ungulatus Perrier. 

 (Plate 4). 



In vol. VI of this Journal, p. 103, I published a short 

 description of Ac. Schlegelii from Liberia; having only a 

 single badly preserved specimen at my disposal, my exa- 

 mination could be but very incomplete. Ever since our know- 

 ledge of the genus Acanthodrilus much increased owing 

 to Beddard's careful account of the anatomy of three New- 

 Zealand species. I was therefore very glad to receive through 

 the care of my colleague Mr. Biittikofer another better 

 preserved individual of the same species, now being able 

 to fill up the gaps in my first description and to figure 

 some of the principal details of the anatomy of this worm. 

 I could also examine several specimens of Ac. ungulatus 

 Perr., which Mr. Layard was kind enough to forward to 

 me from New Caledonia ^). 



The specimen of Ac. Schlegelii measures about 350 m.m. 

 in length, the number of its segments being 327. There 



1) Beddard received also through the care of Mr. Layard several Acan- 

 ^^rfrJ/««-specimens from New Caledonia, and though he states that these worms 

 «may he identical with one or other of the two species {^Ac. ungulatus and 

 Ac. obtusus), first described from that region by Perrier," and that they 

 agree in several characters viz. the position of the clitellum, the form of the 

 penial setae , with Ac. ungulatus , nevertheless he figured them under the name 

 of Ac. Lamrdi (Proc. Zool. Society, 1886, p. 168, pi. XIX). The most im- 

 portant differences between Ac. ungulatus and his specimens he points out, 

 are the situation of the male genital pores and of the spermathecae; for 

 Perrier stated that Ac. ungulatus has the male genital openings situated on 

 the 18th and 20th ring, whereas in Beddard's and our specimens, like in the 

 other known species of Acanthodrilus , they lie on the 17th and 19th seg- 

 ment. The spermathecae should be placed in segment 8 and 10, in stead of 

 in segment 8 and 9, as found by Beddard and myself I suppose that Perrier 

 has only been mistaken in the number of the segments, 1° because he had 

 but a single small specimen at his disposal, 2° because, through the state of 

 contraction of the worm, it is often very difticult to determine the real number 

 of a segment, as proved by Beddard himself, who corrects in this paper several 

 statements he made before. Therefore I am convinced that the worms, sent 

 to us by Mr. Layard, really belong to Ac. ungulatus Perr. 



^otes from the Leyden IMuseum, "Vol. IX. 



