330 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
author’s previous conclusion ; now, however, he maintains that there are 
fourteen. But the fourteen are derived from a primitive twelve, so that 
Piscicola forms no exception to the rule of three which persists among 
Ehyncho bdellidfe. 
Phymosoma varians.* * * § — Mr. A. E. Shipley has published an account 
fuller than that which we have already ^ noticed of the structure of this 
Gephyrean. He now, further, urges that there are reasons for main- 
taining PJioronis in its old position as a form closely allied to the more 
normal Gephyrea inermia. In addition to points already emphasized by 
Lankester, he urges that the skeletal tissue found in Phymosoma has its 
homologue in Phoronis, while the thin membranous web which forms the 
“ collar ” of Phymosoma appears to correspond very closely with the calyx 
or web which surrounds the base of the head in Phoronis, The absence 
in the unarmed Gephyrea of mesenteric partitions in the post-oral body- 
cavity may be accounted for by the twisting of the intestinal loop in tho 
more normal genera ; and the radial muscles are, in all probability, the 
remains of a mesentery which, in the ancestral form, was continuous. 
j3. Nemathelmintlies. 
Filaria sanguinis hominis.J — Prof. C. Sibthorpe gives a short 
account of this worm, and figures drawings made by Prof. A. G. Bourne ; 
the latter adds a description of his preparations. One is that of the 
caudal extremity of the male which has never yet been described. The 
spicules would appear to dilfer from those of any known nematode. 
The Nematode of Beetroot.§ — Dr. J. Ritzema Bos writes the history 
of the beetroot disease, as elucidated by the researches of Kuhn, Strubell, |j 
and others. Millipedes such as lulus, beetles such as Atomaria linearis, 
fungi such as Sporidesmium putrefaciens and Peronospora schachtii were 
knowm to attack the beetroot, but the prevalent disease was usually 
regarded as a consequence of soil-exhaustion by continuous beetroot 
crops. With great patience Kiibn demonstrated that this was not the 
real cause, and Strubell, by tracing the disease to a nematode parasite — 
Eeterodera schachtii — verified the opinion which even in 1859 was ex- 
pressed by Scliacht. This worm is not far removed from the genus 
Tylenchus, to which Ritzema Bos has recently given so much attention, 
and has allied species in H. radicicola, which forms galls on many 
plants, and E. javanica from the sugar-cane. A discussion of its 
characters and life-history (already recorded in this Journal) forms the 
second part of the present paper, w^hich closes with an account of pre- 
ventive measures. 
Nematodes in Vinegar.^i — Dr. G. Lindner discusses the occurrence 
and hygienic imjDort of the AnguillulidaB which are common in weak 
or impure vinegar. They are “ monogenic,” and included among the 
Rhabditidee. The males and females respectively measure 1-1 * 5 mm. 
* Quart. Journ. Micr. Sci., xxxi. (1890) pp. 1-28 (4 pis.). 
t See this Journal, 1889, p. 642. 
X Proc. Roy. Irish Acad., i. (1889) pp. 202-5 (1 pi.). 
§ Biol. Centralbl., ix. (1890) pp. 673-83, 705-16 (11 figs.). 
11 See this Journal, 1888, p, 737. 
Centralbl. f. Bakteriol. u. Parasitenk., vi. (1889) pp. 633-8, 663- 8, 694-9. 
