64 Proceedings of the Royal Physical Society. 
nants of the mouth of the invertebrals) , occupy the sella tur- 
cica, the ethmo-frontal forming the labrum, the sphenoid 
and presphenoid the mandible, the parietal and wormi-otic 
the maxilla, and the occipital the labium. The h^emaxis 
runs along the upper part of the segment above the visceral 
cavity. 
In the vertebrate classes, the relation of these axes is 
inverted. The neuraxis, above the intestinal tube, wliicli 
is no longer found to pass through a ring in the neuraxis 
after the vertebral kaulon has been interposed, and the 
hsemaxis in the visceral cavity on the ventral aspect. 
III. Notes of a Fireball [or supposed Aerolite) recently observed near 
Auchterarder, Perthshire. By John Alexander Smith, M.D. 
In the beginning of the month of February the following 
notice appeared in the Edinburgh newspapers 
''Aerolite. — A few days ago, while Lieutenant- Colonel Hunter of 
Aucliterarder was out taking a walk over his estate, he saw an aerolite 
deseend upon the farm of Drumtersal, occupied by Mrs M'Ewan. The 
sun had just gone down, and the sky was clear at the time. He 
describes its appearance as strikingly beautiful, exhibiting a most 
brilliant light, not unlike a red-hot twenty-four pound ball. It fell slowly 
to the ground, and at the same time a larger body passed over to the 
north east, in the direction of Trinity Gask. The Colonel, who was 
within a few hundred yards of the one which fell, marked the place of 
its descent, and it was got two days thereafter by his gamekeeper. At 
the place where it was found, the grass was burned up for a few inches 
around. It is now at Auchterarder House. It weighs upwards of ten 
ounces, and appears to have been detached from a larger mass. Another 
aerolite is said to have fallen near Stirling on the same evening." 
Lieutenant-Colonel Hunter has since favoured me with 
more correct details of the fall of this fire-ball. It occurred, 
he informs me, on Tuesdaj^, the 27th of January, at five 
minutes to 5 p.m. The day had been beautifully bright with 
sunshine ; the sun, however, had set for eighteen minutes, 
but it was still full daylight, when his attention was attracted 
by the descent of a luminous body, which w^as most brilliant. 
Its fall was nearly perpendicular, and had all the appearance 
of a hot twenty-four pound cannon-ball. It fell apparently 
towards a lea field ; and Colonel Hunter's gamekeeper, who 
happened at the time to be at some distance ofi" in another 
direction, also saw it fall apparently in the same field ; and, 
