ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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Two kinds of nerve-fibres which it is impossible not to distinguish 
are regularly given off from the lateral trunk; each kind can be followed 
as far as the ganglion-cell. It is easy to suggest that the thin fibres 
are sensory, and therefore the smaller ganglion-cells are also sensory, 
while the thicker fibres arising from the larger cells are motor. 
The proboscis is provided with a well-marked nervous system, 
remarkable for the presence of unipolar ganglion-cells ; this is regarded 
as a brain. If we ask how a brain is to be distinguished, we can merely 
answer, only by its relations to the sensory organs, and not by its 
constituent elements themselves. In the Nemertinea the nervous primi- 
tive organs have not exclusively concentrated themselves into an organic 
system of brain and lateral trunks, but are distributed over the whole 
body and its organs. 
Eyeless Species of Oerstedia.* * * § — Dr. G. du Plessis calls attention to 
the fact that the Oerstedia described by Claparhde, the O. pallida of 
Keferstein, as well as a new species from Nice, which ho calls O. auran- 
tiaca, are all eyeless, and all have otocysts ; while they agree in living 
in the damp soil near the edge of the water. It would bo well, he thinks, 
to accept Diesing’s proposition to assign them to the genus Typhlo- 
nemertes. 
Victorian Land Planarians.f — Prof. W. Baldwin Spencer has some 
notes on a collection of twelve species of Victorian Land Planarians, two 
of which are new ; these he calls Geoplana dendyi and G. frosti. 
He observes that, with regard to colour markings, the laud Planarians 
as yet known in Victoria may be clearly divided into three main groups. 
The first has a uniform light tint all over the body, varying in different 
localities from white to orange, or a warm shade of grey. The second 
contains the dark coloured varieties, in which the upper surface of the 
body is blue, green, or brown ; some of them have the ventral surface 
light, and others dark. In the third group are light-coloured varieties 
marked dorsal ly by dark stripes ; some have a median and therefore odd 
number of stripes, and in others there is no median dark stripe. 
Planaria alpina.J — Herr A. Collin gives an account of a Planarian 
found at Sachsa in the Harz district, which appears to be the P. alpina 
described by Dana in 1766 ; the English P. arethusa of Dalyell is pro- 
bably the same worm, as the Japanese P. abscissa of Ijima certainly is. 
Notes on Entozoa.§ — -The late Prof. J. Leidy, in recording the 
presence of Distoma crassum in the Deer and Ox, suggests that there may 
be some relation between the occurrence of this parasite in the United 
States and the influx of a Chinese population. The facts coincide with 
the first discovery of Trichina in Man in England, and its subsequent 
discovery in the American hog. The Guinea-worm is believed to have 
been introduced into tropical America with the Negro from Africa. The 
larger variety of Sclerostomum armatum is reported from the lungs of a 
Horse, in which animal the parasite is generally found in the intestine. 
Some notes are given on the characters of Ascaris anoura. 
* Zool. Anzeig., xiv. (1891) jip. 413-6. 
f Proc. Roy. Soc. Victoria, iii. (1891) pp. 84-93 (2 pis ), 
j SB. Ges. Naturf. Freunde, 1891, pp. 177-80. 
§ Troc. Acad. Philadelphia, 1891, pp. 234-6. 
