90 Mr. H. N. Moseley on Peripatus novje-zealandiae. 



than that described by Mr. BuUar as the third, but be difficult of 

 detection. It is difficult to sec why what appear to be sper- 

 matophores, or portions of such, should be formed in a self- 

 impregnating animal ; and the immobility of the spermatozoa 

 observed is a fact quite as much in favour of these having 

 been introduced for some time and tired out, as freshly deve- 

 loped and functionally active. Surely it is quite possible 

 that in such a case as that of Cymothoa oestroides, which 

 Mr. BuUar cites as unable to swim, active males may exist, 

 Avliich have not yet been detected. The rudiments of both 

 external and internal male organs may well exist in a female 

 Isopod ; and it is significant that the double penis is present 

 only in the earlier stage in development of the Isopod in 

 question. It is quite possible that Mr. BuUar has observed 

 testis-cells and the actual development of spermatozoa in his 

 Isopods, but has not described their occurrence. If so, it is to be 

 hoped that he will not omit to do so in some further account 

 of his most interesting researches, and thus set aU doubt as to 

 his conclusions at rest. 



With regard to my own observations on P. novce-zealandtce, 

 I may mention some further facts. P. tiovcc-zealandice differs 

 from P. cajjensis in that it has 15 pairs of ambulatory members 

 and no anal papillae. There is further in the New-Zealand 

 species a distinctly prolonged but short conical tail, with a 

 slight knob-like enlargement at its extremity, which does not 

 exist in P. ccq^ensis ; further, the anus being terminal, the 

 vulva is separated from it, and situate at a considerable in- 

 terval further forward and between the last pair of members. 

 The two orifices are close together in the Cape species. In 

 P. novce-zecdandke^ and probably also in P. cape7isis, there is 

 present, in addition to the jaws, a single mesially placed row 

 of veiy small simply conical chitinous teeth on the roof of 

 the mouth, running from before backwards. The antennas 

 are in P. novce-zealandice provided at the tips with tactile 

 hairs. The place of commencement of the rectum appears better- 

 defined in P. novce-zealandke than in P. capensis ; and the 

 viscus is longitudinally plicated. 



The ovarian ova of P. novcc-zealandice, apparently ripe, 

 were ovoid in form, 1 millim. in length, filled with oily par- 

 ticles, and with a germinal vesicle and spot. When pressure 

 was made on the covering-glass the egg-membrane was seen 

 to be tough and elastic, and only gave way after the egg had 

 been distorted into various forms. When the contents finally 

 escaped by rupture, the germinal vesicle made its way out, 

 becoming elongated and altering its form in order to pass the 

 aperture in the membrane ; but it resumed its shape again when 



