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SUMMARY OF CURRENT RESEARCHES RELATING TO 
socialis ; and he now publishes notes of his observations. He has failed 
to find any traces of the circular muscular bands which so many 
observers have seen in optical section in Melicerta and Lacinularia. He 
has only found one pair of muscles in the mastax ; these appear to draw 
the rami upwards and inwards, and on their relaxation the rami are 
forced upwards by a semicircular band, which arches over the dorsal 
region. In Brachionus rubens the flame-cells are of considerable size ; 
each consists of a hyaline cylinder, the extremity of which is rounded 
and closed, while a single nucleated cell forms the distal termination. 
A tapering broad-edged cilium springs from the centre of this cell and 
projects forwards about as far as the junction of the flame-cell with the 
lateral canal ; this junction is marked by a fine granular deposit on the 
walls of the canal. These notes are fully illustrated. The author 
remarks that while he found Rotifers in abundance in Epping Forest, 
he was astonished at the absence in any quantity of all but Brachionus 
rubens in the neighbourhood of Falmouth. 
Dasydytes bisetosum.* — Mr. P. G. Thompson calls attention to the 
neglect of the order Gastrotricha in England, and describes a new species 
which he found in a pond near Leyton stone in Essex. It appears to be 
most nearly allied to D. longisetosum, but is nearly twice the size, and 
has much more conspicuous caudal bristles. It is quite colourless, and, 
exclusive of the caudal setae, measures 1/170 in. 
A Multicellular, Infusorium-like Animal.! — Prof. J. Frenzel has 
found in the Argentine Fauna a somewhat remarkable organism. With 
a general resemblance to one of the Ciliates, it has a well- differentiated 
enteric tract and a single cell-layer. Tubular in form, tapering 
anteriorly and posteriorly, it is so flattened from above downwards as to 
be bilateral ; the lower surface is flat, and the upper slightly curved ; 
the former has fine cilia, by means of which the creature moves actively 
forwards, while it is also capable of worm-like or snake-like coils. 
The dorsal and lateral parts are not ciliated, but carry some short setae. 
There is an anterior oral and an exactly terminal finer anal orifice. 
Longer and stronger cirri surround the former. There is no definite 
cuticle, but the cell-membrane is thicker externally than elsewhere. 
The wall of this tubular organism is formed of a single layer of 
rather large, almost cubical cells, which leave a cylindrical lumen 
closely packed with foreign bodies ; this is the enteric cavity. The face 
of the cells turned towards the lumen is finely ciliated. The mouth, 
which is not terminal, is overhung by a cell. 
These animalcules were found of various sizes ; growth is effected 
by doubling of the cells by division. Reproduction is effected by 
transverse division or by conjugation and encystation, when the contents 
of the cyst become all similar cells. 
Echinodermata. 
Classification of Echinodermata.}; — Prof. F. Jeffrey Bell in his 
observations on the arrangement and inter-relations of the classes of the 
* Sci.-G ossip, 1891, pp. 160-2 (2 figs.), 
t Zool. Anzeig., xiv. (1891) pp. 230-3. 
j Aun. aud Mag. Nat. Hist., viii. (1891) pp. 206-15. 
