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SUMMARY OF CURRENT RESEARCHES RELATING TO 
concludes with an account of the anatomy of the excretory organs, and 
remarks that the crystalloids have not the pentagonal dodecahedral form 
described by Hallez in Mesostomida. 
Hew Land Planarian.* — Prof. F. Vejdovsky gives the name of Micro- 
plana Immicola to a new genus of Land Planarians which he has discovered 
in Bohemia. One of its chief characters is the absence of the auricular 
appendages which are so common on the anterior part of the body in 
most of the Dendrocoela indigenous to that country. However much it 
may be contracted, its anterior part always remains rounded, as in rhab- 
docoelous Turbellaria. It is quite transparent, but less so when young 
than when adult, owing to the former retaining in their intestine the 
debris of vitelline cells. The animal is ciliated on the ventral surface 
only, and the cilia are very short ; in this point it resembles Geodesmus, as 
described by Moseley. The cuticle is very fine, elastic, and so resistent 
as to allow for some time the pressure of a cover-glass. The epidermis 
is of the same thickness throughout its whole extent, and the elements 
of which it is composed are generally filled with a clear, almost hyaline 
protoplasm ; at the hinder end of the body some of the cells appear to 
be glandular. It is by the aid of the secretion produced by these glands 
that the animal fixes its hinder end. The secretion is of a mucous nature. 
The rhabdites vary in size and disposition, according to the part of the 
body examined. The larger rods found at the anterior end are so 
closely packed that it is impossible to make out the true structure of the 
epidermis. Their arrangement, in fact, recalls that found by lijima in 
the American Geoplana. This conversion of the epidermis into a sort 
of cuirass affords support to the view that the rods are organs of susten- 
tation which strengthen the fine and delicate skin. 
The eyes are situated over the anterior lobe of each half of the 
cerebral ganglion ; they are very small, black spots, situated below 
the epidermis. Young individuals have no lateral diverticula to their 
stomach ; and these only appear gradually. In the adult the diverticula 
are sharply separated from one another. The excretory organs, or 
pronephridia as the author calls them, belong to the second of the two 
types of these organs which the author recognizes ; in the first, the 
terminal part has no vibratile flame-cells, while in the second the pro- 
nephridiostomata have such cells. In the new genus these are to be 
found in the peripheral region of all parts of the body ; they are uni- 
cellular organs, the enlarged upper end of which is provided with a nucleus 
surrounded by protoplasm ; the narrower part is drawn out into a fine 
canaliculus, the course of which could not be followed were it not for its 
ciliated lining. This canaliculus is formed of a series of cells set end 
to end, each of which has a vibratile flame, and corresponds to a 
pronephridiostome. 
Microplana has two pairs of testes, which are rounded in form and 
situated between the thirteenth and fifteenth diverticula of the stomach ; 
the animals are almost mature in September ; the author is unable to 
speak definitely of the relation of these gonads to their ducts. The 
penial apparatus is pyriform and much simpler than that of Planaria 
subtentaculata or other freshwater Dendroccnla. On its outer surface the 
* Kev. Biol, du Nord de la France, ii. (1889-90) 20 pp. (sep. copy) 2 pis. 
