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SUMMARY OF CURRENT RESEARCHES RELATING TO 
occur on the endothelium of all the parapodia which are distinctly 
biramose; in the mature males there are 4-5 pairs of seminal ducts, 
expanded into seminal vesicles, and probably modified nephridia, each 
with an external aperture and an opening into the body-cavity. The 
ovaries also occur in the forks of the lateral parapodia ; the ova ripen 
in the body-cavity and are there fertilised. The female genital aper- 
tures are two pairs of transverse slits immediately in front of the nerves 
given off from the neural cord to the fourth and fifth pairs of parapodia. 
Spermatogenesis of Earthworm.* — Dr. W. Voigt notices the occur- 
rence of a distinct peritoneal membrane around the testes which Blom- 
field described as naked. The spermatogemmae are first liberated in the 
8-cell stage. Although the cytophore has no nucleus, and is probably 
not a cell, the apparent presence of nucleus or nuclei may sometimes be 
observed. The author also describes twin spermatogemmae, and some 
other details. 
Tasmanian Earthworms.f — Prof. Baldwin Spencer has published 
preliminary notes on Earthworms collected in Tasmania. The same 
three genera to which the Australian species are provisionally referred 
are all represented in Tasmania, but Prof. Spencer shows that it will 
be necessary to revise the classification, when the collections of 
Mr. Fletcher and himself are sufficiently complete and described. The 
zoologist just named has already described Megascolides tasmanianus , and 
to this single earthworm Prof. Spencer adds two more species of Mega- 
scolides, six of Pericliseta , and ten of Cryptodrilus. Doubtless there must 
be very many yet undiscovered, especially in the well- watered valleys on 
the west coast of the island ; but so far as is yet known the earthworm 
fauna of Tasmania is not so extensive as that of Victoria or New 
South Wales. 
[Regeneration in Earthworms.f — Herr B. Friedlaender has made 
many experiments, the main results of which are the following : — 
Earthworms may regenerate not only a number of anterior or posterior 
segments, but supra-oesophageal ganglia and other parts of the central 
nervous system. The cut stumps elongate until the breach is closed; 
the “regeneration-tissue ” consists apparently of compact masses of 
leucocytes into which the new growths make their way; the healing 
growths all show a reduced diameter, and there are frequent variations, 
such as a double brain, or a multiplication of Leydig’s giant fibres. 
Apart from Leydig’s fibres, which the author, as previously recorded, 
regards as comparable to the medullated nerve-fibres of Vertebrates, 
there are traces of medullary sheaths in some of the ordinary fibres of 
the ventral cord ; in fact, no sharp line of distinction can be drawn 
between medullated and non-medullated fibres. Many of the earth- 
worms were infested with a Nematode, probably Pelodera pellio, in the 
regeneration-tissue and body-cavity, while others of a different species 
occurred in the main ventral blood-vessel. 
Distichopus.§ — Mr. J. Percy Moore gives some welcome information 
on this genus of Enchytrseid worms. The genus was first described by 
* SB. Niederrhein. Ges. Bonn, 1894, pp. 76-80. 
f Proc. Roy. Soc. Victoria, vii. (1895) pp. 33-54 (5 pis.), 
t Zeitschr. f. wiss. Zool., lx. (1895) pp. 249-83 (2 pis.). 
§ Airier. Natural., xxix. (1895) pp. 753-6. 
