geal ten PROCEEDINGS OF SOCIETIES. ALZi7) 
almost infinite diversity of form, colour, and markings. Perhaps 
no other class of objects from the animal kingdom afforded so great 
an absence of uniformity and so much beauty. Among some of the 
most striking were those of the earth mite, which laid discoid eggs 
on stones on the Downs; one of the diptera, which deposited winged, 
honeycombed eggs; or the lace-winged fly, which attached greenish- 
white elliptical eggs by long stalks to the leaves of plants infested 
by Aphides, on which the larve fed. That afternoon he had dis- 
covered that they also fed on the eggs of other creatures, a fact, as 
far as he was aware, neither noticed nor recorded. The eggs of the 
Puss moth looked like minute oranges; the cabbage butterfly laid a 
primrose-coloured egg, somewhat resembling a lobster trap; the 
common blue butterfly’s eggs resembled exquisite ivory carvings, but 
some of the most striking were found among the bird parasites. 
Those of the Bohemian pheasant resembled some of the polycystina, 
those of the ground hornbill were so much like polyzoa that they 
might be mistaken for sea mats. The egg of the parasite of the 
mallee bird of Australia resembled the seed-vessel of the cornflower, 
while that of the Indian black-winged peacock might well be mistaken 
for an exquisite flower. 
Those from which the larve had escaped made good objects; in 
some cases it was necessary to perforate and extract the contents to 
prevent their shrinking; others, after steeping in benzole, might be 
mounted as dry objects. 
The rest of the evening was spent in examining a large collection 
of eggs, &c., provided by Mr. Wonfor, and in viewing some beautiful 
photographs of the eggs of bird parasites. 
It was announced that the next meeting would be “an evening 
on mounting objects,’ when different gentlemen would give practical 
instruction in some of the different methods employed. 
August llth. The President, Mr. T. H. Hennah, in the chair.— 
Mr. W. Olding and Mr. J. P. Smith were elected members. Mr. 
Dennant reported on the last Field Excursion to Steyning, and Dr. 
Hallifax read a paper “On the Vertebrate and Invertebrate Eye 
compared.” He commenced by saying that homology of structure 
with diversity of purpose exists throughout each of the great divi- 
sions of the animal kingdom. 
The fore-extremity—with the same components—is the arm in 
man, the leg in the race-horse, the wing in the bird, the fin in the 
fish, and the paddle in the seal, all different expressions of uniformity 
of plan, but instead of homology, analogy exists between the verte- 
brates and invertebrates. Dr. Hallifax instanced the wing of the fly 
and bird as having the same function, but the former deriving its 
structure from its external, the latter from its internal skeleton. 
The vertebrate eye, in like manner, presents the same homolog 
throughout, and he chose the human eye as his example, as, in addi- 
tion to our knowledge of its anatomy, we have personal knowledge of 
its functions. Aided by a large diagram, he fully explained its struc- 
ture, mentioning that the retina—only about the 3 th of an inch in 
thickness—has five layers, and while the other parts of the eye fulfil 
