1901] MICROSCOPICAL JOURNAL. 109 
angle, an intricate system of capillaries feeding every 
pedicle in the membrane. 
ANTENN# OF CocKCHAFER.—Of all points shown by an- 
tenne, I thing there are notany more peculiar and inter- 
esting than those of the organs of the cockchafer, with 
their leaf-like expansions, folding out upon one another 
like the sticks of a fan. This slide contains two of these 
lamella mounted in balsam. Carpenter (7th edition, 1891, 
_ p. 912) says of these markings: ‘A curious set of organs 
has recently been discovered in the antenna of many in- 
sects, which have been supposed to constitute collective- 
ly an apparatus for hearing. Hach consists of a cavity 
hollowed out in the horny integument, sometimes nearly 
spherical, at others flask-shaped, and again prolonged in- 
to numerous extentions formed by the folding of its lin- 
ing membrane ; the mouth of the cavity seems to be nor- 
mally closed by a continuation of this membrane, though 
its presence cannot always be satisfactorily determined ; 
whilst to its deepest part a nerve-like fibre may be traced.” 
The cavities may be viewed from above under a magnifi- 
cation of 1,000 diameters, and also the aspect they pre- 
sent when seen partly sidewaysat the edges of the lamelle. 
A memoir of the structure by Dr. Hicks is to be found in 
the “Transactions of the Linnean Society,” xxii. page 147. 
_ PaDDLE-LEG oF DytiIscus MARGINALIS.—This needs lit- 
tle notice. Dytiscus marginalis is one of the best-known 
of the beetle tribe. A friend of mine, who has a large 
‘conservatory containing an artificial pond—the waters of 
which, by the way, have developed a remarkably rich 
growth of diatomacew—found a fine large specimen of the 
larval form of this formidable insect that was working 
great havoc among the tadpoles of the aquarium. He 
kept it alive in a glass jar for several weeks, and we were 
able to watch its habits. Its fierceness and voracity cor- 
respond with its repellent aspect. Thisis, of course, the 
