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1907-8.] Notes on some Turbellaria from Scottish Lochs. 
Monotus Morgiensis, but Von Graff believed that its true position was 
amongst the Mesostomida, and therefore changed its name to Otomesostoma 
Morgiensis. The first thorough description of its anatomy was given by 
M. Braun, who recognised its true position, and gave it the name of 
Automolos Morgiensis in a paper upon the Turbellaria of Livland, published 
in 1884. In a quite recent paper in the Zeitschrift fur Wissenschaftliche 
Zoologie for December 1906, Nils von Hof stein has published a somewhat 
lengthy paper upon this form, in which he endeavours to show (1) that the 
worm cannot be regarded as an Automolos, but must be placed in a 
separate genus amongst the Alloiocoela, for which he revives the old name 
Otomesostomum of Graff ; and (2), a point of the utmost general importance, 
that all the ova are fertilised in the germarium long before they have 
reached maturity; 
As regards the first point, the chief differences between Otomesostoma 
and Automolos are — 
(1) In Otomesostoma the oviducts are short and transverse, 
whereas in Automolos the ovaries are anterior to the 
pharynx and long. 
(2) There is no uterus in Otomesostoma. 
Unfortunately, the anatomy of Automolos does not seem to be very well 
known, so that the question cannot at present be settled. 
As regards the second point, the only proof Hofstein gives that the eggs 
are fertilised at such an early stage rests upon two drawings of sections 
of oocytes, in both of which darkly staining bodies lie near the nuclei. 
These bodies, which I also find in my preparations, do present a certain 
superficial resemblance to spermatozoa, but I think they must be identical 
with the vitellogen Schicht or dotter Kern such as has been well figured 
by Bambecke in Pholcus phalangioides. 
Gurwitch, in his Morphologie und Biologie der Zelle (Fischer : Jena, 
1904) remarks that— 
“ Nach den liber einstimmenden Ergebnissen der neuerer Forscher 
besitzen die jungen Oocyten in ihrer sog. vitellogenen Schicht, einer 
sichelformige Plasmaanhaufung welche das Idiozoma der oocyten umgibt, 
und Kappenformig dem Keimblaschen anliegt, die eigentliche primare 
Matrix der Dotterbildung.” 
As a matter of fact, this structure is best defined in the very young 
oocytes, at a later stage it appears to undergo a granular disintegration, 
and at the time when the egg is ready to enter the uterus nothing can be 
seen of it (PI. IV. 3, 4). 
VOL. XXVIII. 
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