250 
reover it contains, as | think any unbiassed person must admit, many 
a detail both as to the life-history and anatomical structure of the para- 
site and the habits of its host, which may be sought in vain in Prof. 
Leuckart’s paper of Oct. 9th 1882. Paper, I say advisedly, for up 
to Oct. 11th the date at which the results of this Prof. Leuckart’s 
last work became accessible to us in Oxford, we had no reason to be- 
lieve that he had advanced further on the right track than to suspect 
L. truncatulus of being one of the intermediate hosts. Indeed in the 
first number of the Archiv für Naturgeschichte 1882 he had selected 
as the result of his researches in the year 1881 a tail-less Cercaria 
out of three forms occurring in L. truncatulus as the probable Fasciola 
hepatica. By an unlucky fate, of the other two remaining forms one 
which was rejected by him as having no possible connection with the 
Liver-Fluke was the very Cercaria which we were already convinced 
was the true object of his search. It was abundantly clear to us that 
unless Prof. Leuckart obtained specimens of L. truncatulus for in- 
fection experiments, and unless his experiments proved successful, he 
was not likely to solve the problem at once. 
In conclusion Prof. Thomas desires me to state that by mention- 
ing the date at which his own research was completed, he meant only 
to claim for himself, as he has a most unquestionable right to do, the 
position of an independent discoverer of the Life History of the Liver 
Fluke. So renowned a helminthologist as Prof. Leuckart can hardly 
grudge at least this honour to a younger worker in the same difficult 
field in which he has himself laboured so long and to such purpose. 
3. Die Wasseraufnahme bei den Mollusken. 
Von Justus Carrière. 
Da ich mir schmeichle, daB die Untersuchung Griesbach’s! 
hauptsächlich gegen mich gerichtet ist, môchte ich mir hier einige Be- 
merkungen dazu erlauben. Zunächst bedaure ich, daß Griesbach’s 
Arbeit schon so frühe abgeschlossen wurde, daß er meinen im vorigen 
Herbste erschienenen Untersuchungen über die Fußdrüsen der Cephalo- 
phoren keine Aufmerksamkeit mehr schenken konnte; es hätte dies 
vielleicht einigen Einfluß auf seine Darstellung gehabt. Deshalb will 
ich aber ebenfalls nur meine frühere Mittheilung? zur Vergleichung 
heranziehen. Dann möchte ich zuerst auf einen Satz Griesbach’s 
! Über das Gefäßsystem und die Wasseraufnahme bei den Najaden und Myti- 
liden von Hermann Griesbach. Zeitschr. f. wiss. Zool. 38. Bd. 1. Heft. 1883. 
2 Die Drüsen im Fuße der Lamellibranchiaten. Arbeiten aus dem zool.-zoot. 
Institut Würzburg. 5. Bd. 
