May 9, 1912] 
rocks of Brawdy, Hayscastle, and Brimaston (Pem- 
brokeshire). The district lies about eight or ten 
miles to the east of St. Davids, and consists of pre- 
Cambrian plutonic and volcanic rocks intimately 
associated with sedimentary rocks of the Cambrian 
system. The pre-Cambrian igneous and pyroclastic | 
rocks are brought to the surface along an anticlinal 
axis which ranges in an east-north-easterly and west- 
south-westerly direction; they are divisible into two 
classes, an older volcanic series and a newer plutonic | 
and hypabyssal series. The Cambrian has _ been 
divided into two main groups, the Welsh Hook 
group below and the Ford beds above. The Welsh 
Hook group consists of basal conglomerate, green 
sandstones, red shales, and purple sandstones. The 
position of the Ford beds, which are mostly shales, 
is not so certain. The basal bed of the Cambrian 
apparently rests upon rocks of different ages in 
different parts of the district, and indicates that: the 
Cambrian reposes unconformably on a complex series 
of tuffs and lavas and of plutonic rocks intruded into 
these voleanic rocks. The structure of the district is 
that of a horst, faulted on all sides and surrounded 
by much younger beds. Much of the faulting is of 
pre-Carboniferous age.—Prof. O. T. Jones: 
geological structure of central Wales and the adjoin- 
ing region. This paper deals with the structure on 
a large scale of an area of about 1800 square miles, 
comprising the western portion of Wales, and is 
accompanied by a map, based partly on personal 
observations and partly on information gathered 
from various publications. There are two principal 
anticlinal axes, which follow in the main the valleys 
of the Teifi and the Towy, and are named after these 
rivers; between them is an important syncline (the 
central Wales syncline) which coincides nearly with 
the principal watershed of central Wales. Both the 
anticlines can be traced towards Pembrokeshire, but 
cannot be distinguished beyond the northern boundary 
of the area. The syncline becomes more important 
in a northerly direction, but is lost towards the south- 
west. The variation in the pitch accounts for the 
form of the outcrops. 
Royal Anthropological Institute, April 23.—J. Reid 
Moir and A. Keith: Human skeleton found under a 
stratum of chalky boulder clay near Ipswich. The 
skeleton was discovered on October 6, 1911, at a depth 
of 43 ft. below an undisturbed stratum of decalcified 
chalky boulder clay in the brickfield of Messrs. Bolton 
and Laughlin, about one mile north of Ipswich. The 
stratum of boulder clay under which the skeleton lay 
is part of the great sheet of chalky boulder clay found 
in East Anglia. The skeleton was embedded at the 
junction of the boulder clay and the underlying strata 
of mid-glacial sands, and the section of the strata 
showed no sign of having been disturbed, and it was 
therefore inferred that the skeleton must have been 
in situ before the deposition of the chalky boulder 
clay. 
mid-glacial sands on which the skeleton lay repre- 
sented an old land surface. In these strata and in 
the overlying deposits of boulder clay he had dis- 
covered flint implements which, in the opinion of M. 
Rutot, belonged to the pre-Strépyean type. The 
skeleton lay on its right side, in an ultra-contracted 
posture; nothing was found with the skeleton; there 
was no evidence of burial. The skeleton was that of 
a man about 1800 metres (5 ft. 10 in.) in height, and 
probably between thirty and forty years of age. In 
the characters of the skeleton and skull the remains 
resembled modern man, and showed none of the 
marked features of Neanderthal man. The skull is 
estimated to have had a maximum length of 192 mm., 
maximum width 144, auricular height 111, cephalic 
index 75. The only peculiar feature was found in the 
NO. 2219, VOL. 89] 
The | 
In Mr. Moir’s opinion, the upper part of the | 
NATURE 
252) 
shape of the tibia. In place of the anterior border 
being raised into a ridge or crest, it was flat, thus 
differing from all known tibia, ancient and modern. 
In the opinion of the speakers, the modern type of man, 
as represented by the Ipswich skeleton, the Galley 
Hill skeleton, the Bury St. Edmunds cranial frag- 
ments, and by numerous human remains found in 
France, was evolved long before the Neanderthal type 
of man became extinct in Europe. 
Zoological Society, April 23.—Dr. S. F. Harmer, 
BIRSSt)) |vice-president, -in, the  chair.—€:; (HE 
O'Donoghue: The circulatory system of the common 
grass-snake (Tropidonotus natrix). Several interest~ 
ing features correlated with the loss of limbs and the 
elongation of the body were stated to occur in the 
blood-vessels. The vessels, like the viscera they sup- 
plied, were asymmetrical; not only were those on the 
right anterior to those on the left, but they were also 
noticeably larger. No indication of the descent of 
snakes from a limb-bearing ancestry was to be found 
in the circulatory system, save perhaps a small pair 
of veins which might correspond to the pelvic veins 
in Lacertilia.—Julian S, Huxley: The courtship of the 
redshank (Totanus calidris). The first purpose 
of this paper was to direct attention to the 
many valuable results to be obtained by simple 
watching of very common British birds; and 
the second was to show how the facts observed 
in the redshank bore on the theory of sexual 
selection. In this species there was no rival display 
between several males at once: a single female was 
courted by a single male, as in man. But in quite 
go per cent. of observed courtships the female rejected 
the male, either during the pursuit or during the dis- 
play, by simply flying away. Thus the consent of 
the hen was absolutely necessary if pairing were to 
take place, and this consent was usually withheld; in 
other words, selection by the female was a reality in 
the redshank. Other interesting points were as fol- 
lows :—The plumage of the two sexes was identical, 
and was decidedly cryptic when the birds were at rest. 
During flight the white underside of the wings and 
the white tail were conspicuously revealed, and prob- 
ably served as recognition marks. The significance 
of the red legs was unknown. During display the 
male directed attention to the underside of the wings 
by raising and vibrating them, to the tail by fanning 
it out, and to the red legs by his slow, high steps; 
| besides this he uttered a note heard at no other time. 
Thus, since the actual colours and structures used in 
display were found in both sexes, the only peculiarly 
male possession—the only secondary sexual character 
of the redshank—was a special behaviour, devoted to 
showing off these common colours and structures in 
a special way. This seemed to show that secondary 
sexual differences in birds were originally differences 
of behaviour, and that only when these were estab- 
lished did differences of colour and structure come 
to be developed.—Mrs. E. W. Sexton: Brackish-water 
Amphipoda from Bremerhaven. Special reference was 
made to a new species of Gammarus, which inhabited 
both fresh and brackish water, and was interesting 
as showing in a marked manner the effects of environ- 
ment on development.—C. Tate Regan: Descriptions 
of ten new species of South American fishes of the 
family Loricariide in the British Museum collection. 
Challenger Society, April 24.—Dr. E. J. Allen in the 
chair—Dr. H. Muir Evans: Poison organs and 
venoms of poisonous fishes. After reviewing previous 
work, the author pointed out that the researches of 
Briot were incorrect, and that this observer had 
obtained his results by means of a filtered glycerine 
extract of the spines of Trachinus (the weever). Dr. 
Evans had used fresh venom for his experiments, and 
found that haemolysis took place with fresh venom 
