INTERESTING FACTS REGARDING THE HISTORY OF THE WASP. 
127 
the opinions of various philosophers in refer- 
ence to the subject, and then supplies us with 
inferences drawn from his own experiments. 
D’ Alembert admitted the want of achroma- 
tism in the eye, but considered the aberration 
very small. Euler held an opposite opinion, 
and Dr. Maskelyne refuted the arguments of 
Euler. Dr. Wells has observed that the eye 
has no principle of achromatism, and Sir 
David Brewster says that “no provisionis made 
in the human eye for the correction of colour, 
because the deviation of the differently coloured 
rays is too small to produce indistinctness 
of vision.” Mr. Coddington states that 
the eye, when employed in its natural and pro- 
per manner, is achromatic. The fact is, that 
we see objects without the slightest degree 
of pi-ismatic colour or indistinctness. The 
question then is, how can this be reconciled 
with theoretical considerations ? Mr. Powell, 
by ingenious calculations, has inferred that 
in such a combination as the eye, exact achro- 
matism is perfectly possible in theory, and 
that the principle of its achromatism, although 
not effective in oblique excentrical rays, may 
be in general achromatic for direct rays. He 
give^ the results of a series of experiments, 
in which he has “endeavoured to ascertain 
directly the actual prismatic dispersions of 
the crystalline, and vitreous humours, by mea- 
suring micrometically the separation of the 
different parts of the spectrum of a line of 
light produced by looking through a prism 
formed of each medium, from the eye of an 
ox, between inclined glass plates.” From 
which he concludes “ that the media of the 
eye have as neaidy as possible those disper- 
sive powers and relations of indices for the 
different rays, which theory requires for pro- 
ducing achi-omatism by means of a single lens, 
when the focus is formed in a dense medium,” 
Mr. TWISS of UNIVERSITY COLLEGE 
EXHIBITED SOME SPECIMENS OF 
THE PAPYRUS FROM SYRACUSE. 
Fehruary 1.3, 1835. — Both in its natural 
and manufactured state. He read some obser- 
vations upon it, describing the locality 
where the plant grows on the banks of a 
small stream issuing from the fountain of 
Cyane, near Syracuse. It is now manufac- 
tured merely as a curiosity. 
Some discussion took place on the sup- 
posed identity of the pap 3 u-us with the lotus. 
Mr. TWISS EXHIBITED TO THE SO- 
CIETY A SERIES, ALMOST COM- 
PLETE, THE SILVER AND BRONZE 
COINS OF THE ROMAN REPUBLIC, 
AND READ A DISSERTATION UPON 
THEM. — In this paper the author com- 
mences with observing the gradual decline in 
weight of the As from the time of the kings 
through the successive ages of the republic. 
The value of the copper is compared with 
that of the silver coinage ; and the author is 
of opinion that the rise in the value of copper 
is chiefly accounted for from the diminution 
of the supply, both from the exhaustion of 
the mines, and the interruption of the com- 
merce with the Carthaginians, as well as 
from the circumstance of copper being 
re-exported to Sicily; these causes acting moi^ 
powerfully about the time of the second Punic 
war, when the As was diminished to an 
ounce, from its original weight of ten ox- 
twelve. The last diminution, to half an 
ounce, took place in the time of Sjdla. Sil- 
ver was introduced into the currency after 
the conquest of Compania and Lower Italy. 
Obsei’vations are made on the silver coinage; 
and particularly on the devices appearing on 
them : and the author then gives a general 
sketch of theiinancial arrangements, and state 
of the currency, at successive periods of the 
Roman history. 
A PAPER WAS READ BY THE REV. 
E. T. BIGGE OF MERTON COLLEGE 
ON THE NATURAL HISTORY OF 
THE WASP, 
February — The object of this paper 
was to correct the mistakes into which several 
writers have fallen, and to state the results 
of the author’s own observations on two spe- 
cies, the. Vpspa Vulgaris and Vespa Britan- 
nica. 
The former is common in all parts of the 
kingdom ; the latter, though occasionally 
met with in the southern coxxnties of Eng- 
land, is abundant in the northern districts, 
and in Scotland, as well as in the northern 
parts of Europe, The V Vulgaris of Lin- 
neus is the V Britannica, the French having 
called tiiat species vulyaris, which was most 
common, and which formed its nest in the 
groxxnd. The V Vulgaris of the present 
entomologists is the'V Gallica of Linneus. 
Leach gave the name Vespa Britannica to 
the tree wasp. The points of difference 
beween the two species are as follows : — 
1. The ti-ee wasp (V Britannica) has a red- 
dish-bi'own spot near the point of insertion 
of the wings, which is seldozn visible in dried 
specimens, 
2. In the males and neuters the base of the 
antennae is yellow on the outer side, instead 
of being entirely black, as on the ground 
wasp, but the females often present excep- 
tions to this distinction. 
3. The tree wasp has two yellow spots on 
the back part of the corslet, while the ground 
wasp has from foxir to six, 
4. The spots on the abdomen of the tree 
wasp are not so much detached from the 
black bands as in the other scocies, and less 
so in the males than the females . Linneus 
drew a distinction between the hornets (V 
Crabro) and the true wasps, founded on these 
marks, which cannot be considered as decisive, 
because they vary in different individuals. 
5. The tree wasp has more black upon the 
body generally than the other species. 
6. The tree wasp is rather lai-ger. 7. The 
organs of generation in the males of the two 
species vary considerably. 8. The abdomen 
in each species contains the same number of 
x-ings, viz. six in the females and neuters, and 
seven in the males. 
Mr. Bigge states some intei-esting facts in 
illustration of the natural history of both 
species. Societies of wasps, as of bees, con- 
sist of three different classes of inhabitants, 
males, females, and neutei-s. The females, 
which are much larger than the others, are 
