202 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
author has confirmed the conclusions of Erichson and Siebold as to the 
presence of a true cephalothorax. He gives a figure of Xenos Bossii 7 
showing (a) the supra-oesophageal ganglion with its optic lobes, (b) the 
oesophageal nerve-ring, (c) the sub-oesophageal ganglion, and (d) the 
abdominal ganglion, which is fused with (c) in the larvae, but connected 
with it by a commissure in the adult female. 
Second Abdominal Segment in Libellulidse.* * * § — Miss M. F. Goddard 
describes the second abdominal segment and the penis in a few male 
Libellulinae, species of Diplax, Celithemis , Libellula , and Plathemis. 
Some general suggestions are offered — e.g. that the hamules may be 
homologues of abdominal appendages ; and that the bifid condition of 
the hamules in Libellulinae is secondary, transitions occurring towards 
the uniramous condition in the other sub-families. 
Larvae of British Lepidoptera.f — The seventh volume of ‘ The Larvae 
of the British Butterflies and Moths,’ by (the late) Mr. W. Buckler, 
published under the editorship of Mr. G. T. Porritt, deals with the first 
portion of the Geometrae. Mr. G. C. Bignell supplies a list of parasites 
known to affect the species treated of. It is needless to say more in 
regard to this well-known work. 
j8. Alyriopoda. 
Investigations on Biplopoda.J — Dr. C. Yerhoeff discusses — (1) the 
comparative morphology of the first pair of appendages in male Iulidm ; 
(2) the well-marked differences of coloration in the sexes of Brachyiulus 
projectus Yerh., B. projecins var. aliicolus Yerh., and B. rosenauensis < 
Yerh., the males being the darker in all three cases ; (3) the occurrence 
of Schalt-males in Pachyiulus hungaricus Karsch and in Brachyiulus pro- 
jectus Yerh. ; and (4) three new forms from Siebenbtirgen, viz. Poly- 
desmus hamaius Yerh., P. illyricus montanus Daday, and P. illyricus 
Yerh. [= complanatus Daday]. 
Ovum of Diplopoda.§ — Dr. B. Nernec has investigated the structure 
of the ovum of Polyzonium germanicum Brdt., Blaniulus guttulatus Bosc y 
and some other Diplopoda. A medium-sized ovum contains a large 
well-defined cap-like body, on the concave side of which lies the nucleus. 
The latter shows an achromatic reticulum, and a large round nucleus 
including a still smaller body. Beside the cap there is also a much 
smaller corpuscle, around which the plasma is radially disposed (the- 
attraction-sphere). The cap in question arises from one of two cor- 
puscles which lie near the nucleus in the young ovum ; it becomes very 
definite, and embraces the nucleus ; thereafter it becomes vacuolated and 
breaks up. It is possible that cap and sphere are both differentiations 
of an originally single corpuscle which divides. 
5. Arachnida. 
New Spiders.|| — The Kev. 0. Pickard Cambridge describes two new 
spiders, both of which require new genera. The first, Aetius decollates 
* Proc. Am. Philos. Soc. Philadelphia, xxxv. (1896) pp. 205-12 (2 pis.). 
t Ray Society, London, 8vo, pp. xv. and 176, pis. cvi-cxxvii. (1897), volume for 
1894. % Zool. Anzeig., xx. (1897) pp. 78-88. 
§ Anat. Anzeig., xiii. (1897) pp. 309-12 (15 figs.). 
U Proc. Zool. Soc., part 3, 1896 (published 1897), pp. 1006-12 (1 pi.): 
