646 



through the oviduct. In Eudrilus it is still more difficult to understand 

 how this is carried out, if the organ of the 14*^'' segment, which I regard 

 as an ovary, be really the receptaculum ; the ovary is entirely enclosed 

 by a muscular sac as is also the organ of the 11*^'' segment; it is not 

 therefore at all probable that ova are conveyed from one to the other 

 in the way which must take place in 1 Mmhricus . On the other hand it 

 seems improbable that the ova pass down into the spermathecal duct, 

 and then pass up the oviduct into the supposed receptaculum. I am 

 not able to state whether there are cilia in the duct leading from the 

 ovary of the 115''' segment; but the spermathecal duct is certainly with- 

 out cilia as is also the distal half of the oviduct of the 11*^'' segment; 

 the proximal half of the oviduct is abundantly furnished Avith long 

 cilia; but, if the movement of these is such as to further the exit of 

 ova from the ovary of the 1 4*^'' segment they would prevent the entrance 

 of ova into the same organ; the passage of ova from the ovary of the 

 IIH"' segment into the ovary of the M"" segment would also necessitate 

 very complicated changes in the direction of the peristaltic action of 

 the various parts of the female reproductive system. 



All these considerations appear to ])oiut to the conclusion that in 

 Eudril us there are two pairs of ovaries situated respec- 

 tively in the 13'*" and 14*^' segments; each ovary is enve- 

 loped in a muscular sheath which is c on tinuo us with the 

 oviduct; the two oviducts of each side open opposite to 

 each other into the spermathecal duct. The muscular 

 sac investing the ovaries is probably equivalent to the 

 receptaculum of other earthworms. 



2. Bemerkung zu den Mittheilungen von F. Braem über 

 Siifswasserbryozoen (d. Zeitschr. 1888, No. 288, p. 503 ff). 



Von Prof. Dr. K, Kraepelin, ILimburoj. 



cingeg. 10. October 1888. 



Zu den Mittheilungen desHenn Stud. Braem über die Bryozoen 

 des süßen Wassers hätte ich eine ganze Reihe von liemerkungeu zu 

 machen, die sich theils auf die Art und Weise, wie meine Ansichten 

 citirt sind, theils auf die von Herrn Braem geschilderten Thatsachen 

 beziehen. Da ich aber in dem 2. Theile meiner Monographie der Süß- 

 wasserbryozoen Gelegenheit nehmen werde, näher auf diese Puncto 

 einzugehen, so möchte ich an dieser Stelle nur auf eine Thatsache auf- 

 merksam machen, die für mich nicht ohne Werth ist. 



Herr Braem sagt in der Einleitung seines Aufsatzes, daß er Re- 

 sultate gefunden habe, welche »für das richtige Verständnis des Baues 



