ed 
The same effect is witnessed in the case of the so-called fire-ball, 
which sows destruction wherever it strikes; the cause in both 
cases probably being the same, an explosion of a circumscribed 
and confined mass of electricity. 
Friday, February gth. Sir Samuel Wilks, Bart., F.R.S., in 
the Chair. There was a large number of persons present. 
Mr, Montague F, Hopson, F,L.S., F.E.S., read a paper on 
‘‘ British Hawk Moths.” The name given to this group of 
moths is Sphingides. The order Lepidoptera is divided into two 
divisions—(1) Rhopalocera, or those with clubbed antenne, com- 
prising butterflies, and (2) Heterocera, or those whose antenne 
are otherwise. These are the moths among which are the 
Sphingides. 
British Hawk Moths number only seventeen species, and five 
of these are exceedingly rare. A superficial glance is sufficient 
to show their large size and brilliant colouring. The expanse of 
the wings measures from two to six inches. Twelve months usually 
suffices to complete the cycle of change. The eggs are pale green, 
large and ovoid, and are laid in summer on the food plant. The 
larve of most of the Sphingides are beautiful objects and of large 
size. They have six true legs and ten creepers. All seek the 
ground in which to pupate, some burrowing deeply. The pupe 
are roughly conical, with a hornlike projection at the smaller end. 
Their colour is commonly brown, ruby or black. The popular 
distinctive names of our British species are :—the Broad-bordered 
Bee Hawk, Narrow-bordered Bee Hawk, Humming Bird Hawk, 
Elephant Hawk, Silver-striped Hawk, Small Elephant Hawk, 
Striped Hawk, Oleander Hawk, Convolvulus Hawk, Privet Hawk, 
Pine Hawk, Death’s Head Hawk, Lime Hawk, Poplar Hawk, 
and Eyed Hawk Moths. Mr. Hopson gave a detailed description 
of each species and its habits. His paper was illustrated 
throughout by many specimens representing most of the above- 
named species. 
Friday, March gth. Sir Samuel Wilks, Bart., F.R.S., in the 
Chair. There was a good attendance. 
Mr, P. Macleod Yearsley, F.R.C.S., F.Z.S., read a paper 
on ‘* Echinoderms,” with lantern illustrations. He said ‘‘ Echino- 
derm’’ meant prickly skin, for most echinoderms had spines or 
nodules. They were divided into five classes :—(1) Asteroidea— 
the starfishes, (2) Ophiuroidea—the brittle stars, (3) Echinoitdea— 
