Nov. 23, 1882] 
NATORE 
gi 
October 29 at midnight. A real panic is reigning among the 
population of Cascia. The extent of the zone of the phenomena 
cannot yet be ascertained, but it seems that the eruption of 
Mount Etna is closely connected with it. Several old houses 
fell at the first shock. 
THE additions to the Zoological Society’s Gardens during the 
past week include a Bonnet Monkey (M@acacus radiatus) from 
India, presented by Mr, A. S. Gissing ; two Common Herons 
(Ardea cinerea), British, presented by Mr. R. H. Rabbetts ; a 
Common Barn Owl (Strix flammea), British, presented by Mrs. 
A. Wright ; a Slender-billed Cockatoo (Zicmetis ‘enutrostris) 
from South Au-tralia, deposited ; two Red-billed Tree Ducks 
(Dendvocygna autumnalis) from America, a Zenaida Dove 
(Zenaida amabilis) from the West Indies, purchased ; a Hairy- 
rumped Agouti (Dasyprocta prymnolopha) from Guiana, received 
on approval, 
BIOLOGICAL NOTES 
APPARENT BIRD-TRACKS BY THE SEA-SHORE,—At a recent 
meeting (October 3) of the Academy of Natural Sciences of 
Philadelphia, Mr. Thomas Meehan called attention to what 
appeared to be the tracks of a three-toed bird in the sand near 
low water-mark, at Atlantic City. These tracks were of a nature 
that would be readily recognised by observers as bird-tracks ; 
but while thinking of what bird could have cansed them, and 
reflecting on the phenomenon of their being only found on the 
sand near low water-mark, Mr. Meehan noted on the face of the 
smooth, recedins waves, spots where the water sparkled in the 
light, and he found this was caused by little riplets as the wavelets 
passed down over the half-exposed bodies of a small crustacean 
(Hippa talpoidea), and that the water, in passing over the bodies 
made the trifid marks which had been taken for impressions of 
bird’s feet. These little crustacea take shelter in the sand near 
low water-mark, and enter head foremost in a perpendicular 
direction downwards, resting just beneath the surface. The 
returning wave took some of the surface sand with it, and then 
the looser portions of the bodies uppermost in the sand were 
expose !. Often the little creatures would be quite washed out ; 
when recovering themselves, they would rapidly advance in a 
direction contrary to the retreat of the wave, and would enter the 
wet sand again as before, their sides being parallel with the 
shore. Their bodies terminate ia a caruncular point which, witb 
the position of the two hind-legs, offer a tridentate obstruction 
to the sand brought down by the retreating wave, and the water 
passing round the points made the three toe-like grooves, which 
resembled a bird’s foot from one and a half to two inches long. 
The crustacea, in their scrambles for protection beneath the sand, 
imanaged to keep at fairly regular distances from each other, 
and hence there was considerable regularity in the tracks, as if 
they had really been produced by birds. Although the author 
of these notes presented them as a trifle, yet it will be at once 
apparent that they are of great interest. Tr.fid impressions 
like the-e, filled with mud and the deposit then to become solid 
rock, would puzzle, if not altogether mislead, future observer:. 
AUSTRALIAN FRESHWATER SPONGES.—Up to this date, but 
one species of freshwater sponge has been described from Aus- 
tralia, Spongilla capewelli of Bowerbank ; but Mr. W. A. Has- 
well, at a meeting of the Linnean Society of New South Wales 
(May 31, 1882) describes two new species from a pond near 
Brisbane, and one from the River Bell at Wellington. Spongilla 
sceptroides is a green, smooth, encrusting species, with the skeletal 
spicules very slightly curved, acute at both ends, ornamented 
with very minute projecting points. The statoblasts are spheri- 
cal, defended by long, slender, straight, cylindrical spicules, 
which are armed with numerous acute spinules, chiefly collected 
around the extremities, forming heads; it is found growing on 
submerged twigs. 5S. dotryotdes is a yellowish flat-encrusting 
species, with curved skeletal spicules, fusiform, acute, with scat- 
tered, extremely minute, projecting points. Statoblasts protected 
by a crust of short, strongly-curved spicules, with heads at each 
end of numerous short, blunt, or sub-acute spines, somewhat 
botryoidal-like, the shaft smooth. This species was found with 
the first: another species fonnd by Mr. E. P. Ramsay in the 
Bell River, growing on masses attached to submerged timber 
seems nearly related to S. AMeyent, from Bombay. In colour it 
varies from a grass green toa yellow. It is massive, lobulated, 
with oscula between the projections. The skeleton spicules are 
perfectly smooth, and the amphidiscs are provided with from 
one to ten acute and prominent spines. Another species from 
somewhat deep water is indicated by Mr. Haswell. 
EaRTH-worms In NEw ZEALAND.—The following inter- 
esting observations form part of a communication from Mr. A. 
T. Urquhart, to the editor of the Mew Zealand Fournal of 
Science, and appear in the September number of that periodical. 
In October, 1875, I duz a trench on some newly-cleared land— 
a raised beach at Manukau Harbour. The section then showed 
about 44 inches of black mould and a horizontal layer, 1 inch 
thick, of burnt clay, wood-ashes, small stones, and pumice lying 
ona brownish-green arenaceous clay. The vegetation cleared was 
the growth of come thirty years. A portion of the land was 
left undisturbed. Measurements again taken a few days ago 
gave an average depth of 1} inches of turf, 53 inches of black 
mould, and there was no percepiible difference in the layer of 
ash. An angular block of Trachyte—about twenty-five pounds 
in weight—placed in May, 1875, had sunk 1 inch, allowing 
for the turf. As the results of some accurate calculations, as to 
the number of worms per acre, Mr. Urquhart gives results so 
considerably higher than Henson’s, that he would have hesitated 
to publish them, were he not in a position to prove them. 
Henson, it will be remembered by the ‘readers of Darwin on 
‘Vegetable Mould,” calculates that there are 53,767 worms per 
acre in garden mould, and above half that number in corn-fields. 
Mr. Urquhart’s estimates, founded on digging about a quarter 
of an acre, as well as by a large number of tests on various parts 
of the fields, some that were under pasture for over sixteen 
years, gave from four to twenty-six earth-worms per each square 
foot. The alluvial flats, slopes, and richer portions of the upper 
lands would average eight to the square foot or say 348,480 per 
acre. In the uncultivated fern lands worms are scarce, In 
New Zealand worms not only leave their burrows, but climb up 
trees; in search of food, this chiefly in the night time, though 
often until a late hour on damp warm mornings. 
THE GENESIS OF THE HyPOPHYSIS IN PETROMYZON 
PLANERI.—Prof. Anton Dohrn, of Naples, writes:—‘‘ In his 
contributions to the history of development of the Pertromyzons 
(Morphol. Fahrbuch, vol, vii. p. 158), Mr. W. B. Scott says: 
©The organ of smell is one of the most peculiar parts of the 
whole organisation of the Cyclostoms. . . .. The position of 
the organ is a symmetrical from the very beginning. It first 
begins to manifest itself as a shallow depression above the 
mouth, which we may regard as a common depression for the 
nasal cavity and the hypophysis. The ectoderm covering the 
head becomes suddenly thickened at one spot, in order to form 
the special smell sense epithelia which lie close to the front 
extremity of the brain. The cells at the bottom of the depression 
decrease in depth, while the cells that cover the opposite wall 
of the depression (z.e. the continuation of the upper lip) are very 
low.’ Balfour (‘* Comp. Embryology,” vol. ii. p. 358) makes 
the following criticism upon this statement :—‘‘ I have not myself 
completely followed the development of the pituitary body in 
Petromyzon, but I have observed a slight diverticulum of the 
stomodaeum, which I believe gives origin to it. Fuller details 
are in any case required before we can admit so great a diver- 
gence from the normal development as is indicated by Scotts 
statements.” According to researches which I made this summer, 
the question is solved, butin a way different from either Balfour’s 
or Scott’s suggestions. The hypophysis arises rather as an inde- 
pendent depression of the ectoderm between the depre-sions for the 
nose and the mouth. Its connection with the nasal depression 
is only secondary, and is caused by the strong and early deve- 
lopment of the upper lip. It has no connection with the mouth 
depression, because the upper lip develops between the mouth 
depression and the hypophysis. The particulars of these rela- 
tions will appear in the next number of the ‘‘ Studies in the 
Early Development of Vertebrates” in the Proceedings of the 
Zoological Station at Naples (Zoo/. Anzeige, November 6, 1882). 
Formic anp AceTIc AcID IN PLANTs.—Dr. Bergmana 
sums up the results of his investigations as to the occur- 
rence and import of formic end acetic acids in plants as 
follows:—1. Formic and acetic acids are met with as con- 
stituents of protoplasm throughout the whole of the vegetable 
kingdom in the most yarious portions of the plant-organism, 
and both in chlorophyllacesus and non-chlorophyllaceous forms. 
