536 



sponding structure in any known earthworm; but Dr. Rosa does 

 not make use of the characters of the atrium in defining the family 

 Terricolae and so I pass by this point of difference, which appears to 

 me nevertheless to be a very important one. 



In the Xr'' segment oî Moniligasteì- Baricelliis a funnel-like struc- 

 ture composed of columnar ciliated cells which I have identified as an 

 oviduct; as I was unable to find its external pore I cannot be certain 

 that it is not one of a second pair of vas deferens funnels ; but it seems 

 much more likely that the structure in question is an oviduct assum- 

 ing for the moment that the funnels in segment XI are vasa deferentia 

 funnels — one of two things must follow : either they open by means of 

 well developed atria on both boundary lines of segments XI , XII — 

 in which case the conspicuous orifices of them have escaped the atten- 

 tion of Perrier, Horst, Bourne'^ and myself: or, the tubes run 

 forward and open into the atrium of the X^*^ segment ! In the latter case 

 there will be a ressemblance to the Lumbriculida so strong, that any 

 further criticism of Dr. Rosa's views is rendered unnecessary. I think 

 it must be admitted that the ciliated funnels are those of the oviducts 

 and that they open on to the exterior not further back than the XII"* 

 segment; it is a fair assumption that the ovaries are in the XP'* though 

 I confess to having found no traces of them. 



I cannot therefore agree with Dr. Rosa's contention that the re- 

 productive organs of Mo7iiligaster Barivelli conform to the type which 

 he formulates as characteristics of earthworms. 



There is another structural feature in Motiiligaster to Avhich I 

 would direct attention as bearing upon the question at hand. 



Dr. Rosa rightly remarks upon the presence in all earthworms 

 (that have been investigated from that point of view) of a pair of recep- 

 tacula ovorum in the XI V^^ segment attached to the anterior mesen- 

 tery. I have called attention to the fact that in Moniligaster Ilouteni 

 these bodies are of remarkably large size as compared with those of 

 other earthworms. 



Dr. A. G. Bourne has made the interesting observation that in 

 Moniligaster minutus »sacs containing ripe ova occupy segments XII 

 — XV at least«. I cannot avoid the conclusion that these sacs are as 

 Dr. Bourne suggests eggsacs Avhich therefore in the large number of 

 segments which they occupy offer a striking ressemblance to the egg- 

 sacs of the Tubificidae and other aquatic Oligochaeta. 



London, Sept. 5 1889. 



9 Proc. Zool. Soc. 1886. 



Druck von Breitkopf & Härtel in Leipzig. 



