SOLOMON ISLANDS, THE NEW HEBRIDES, AND THE LOYALTY ISLANDS. 185 



seems to be a further specialisation of a terminal sac of varying size into which the 

 duct of the spermiducal gland opens in many other species. In fact we have in this 

 genus an interesting series of stages in the evolution or degradation of this organ. 

 In many species the duct of the spermiducal gland opens directly on to the exterior, 

 in some cases not even widening before its aperture ; in other cases it gets wider 

 towards the external pore. The next stage is seen where the duct opens into a 

 small sac before opening on to the exterior ; in other species again this sac is larger 

 and larger; and finally we have the two forms under consideration in which the sac 

 exists, is large and is furnished with a protrusible or eversible penis. These two 

 species furthermore agree in the fact that the spermiducal gland is bi- or even tri- 

 lobed, each division then having its own separate duct. It does not seem to me to 

 be very plain that there is much difference in the copulatory apparatus of P. arturi and 

 P. malamaniensis. But one point of difference is noted by Benham and that is the 

 form of the spermathecal appendix. In P. arturi it is long, longer than the main 

 pouch, while it is small in P. malamaniensis. For this latter reason I refer examples 

 of a worm which is certainly either one species or the other to P. malamaniensis; 

 they were collected in New Britain on Gazelle Peninsula, on the Isle of Pines (New 

 Caledonia), at Lifu and at Mare in the Loyalty Islands, and finally at Esafate in the 

 New Hebrides. The original description of P. malamaniensis is of specimens from the 

 Philippines. 



Perichaeta Loriae, Rosa. 



P. loriae, Rosa. Ann. Mus. civ. Genova (2), xix. p. 61. 



This form was described by Rosa from New Guinea. I have seen two examples 

 from Guadalcanar in the Solomons. I have only to add to Dr Rosa's account that in 

 one at any rate of these two individuals there were no setae on segments XIV and 

 XV. In the other I observed them upon XV. In both examples there are setae upon 

 segment XVI; but the glandular modification of the integument does not extend so 

 far as the seta row. 



Perichaeta Upoluensis, F. E. B. 



P. upoluensis, Beddard. Proc. Roy. Soc. Edinb., XIV. p. 17-i. 



Nearly twelve years ago I described from Upolu in the Samoa group of Islands 

 a PericlJeta which' I believed, and believe, to be a distinct form. The speeds was 

 mainly characterised by the character and distribution of the genital pa P illae_ Dr 

 Willi collected four examples of tins same species at Esafate or Sandwich Island 

 „, the New Hebrides group. Distant though this Island is from Upolu, I colder 



w. 



