SCIENTIFIC SUMMARY. 
425 
complete passage through the upper jaw throughfwhich it passed, probably, 
at every attempt of the fish to feed. — Dublin Quarterly Journal of Science , 
xiii. p. 50. 
Variation of Species among Rhozopods. — Our best authority upon the 
anatomy and distribution of the animals embraced by the group Rhozo- 
pods is Dr. G. C. Wallich. This observer has contributed several valu- 
able papers to the Annals of Natural History for the past year, which 
should be carefully studied by all protozoan-loving naturalists. His last 
memoir appears in the March number of the Journal alluded to, and in it 
he enters into a description of the forms and relations of the so-called species 
of the genus Difflugia. The great bulk of the species are mere varieties 
of a few definite forms. It seems that in certain species the sarcode matter 
which constitutes the animal has the power, under different conditions, of 
building up different tests or shells. Thus, when in the locality in which 
they are found, one set of minerals is abundant, they select this, and so 
on. They seem in this particular rather to resemble the caddis worm, 
whose habits have been so faithfully pourtrayed by one of our lady 
naturalists, Miss E. M. Smee. The general conclusion which Dr. Wallich 
draws is thus expressed. The animal does not vary ; but it modifies the 
architecture of its habitation , and the mineral material of which that habitation 
is in a great measure constructed in obedience to local conditions , and in the 
manner best fitted to meet its requirements. — Vide Annals of Natural History 
for March, 1864. 
The Habits of the Australian Tree-Frogs are thus described by Dr. 
Albert Gunther, in an article in the 44 Annals of Natural History.” They 
sleep during the day, squatting in a corner, generally selecting a place in 
which they are hidden from view, but easily aroused on the approach of 
some insect, which they seize with their tongue. When the prey is large, 
or when they have accidentally seized a small piece of wood, &c., toge- 
ther with the insect, they use their fore-foot to push the insect into the 
mouth or to remove the object which is unfit for food. They never enter 
the water during the summer months, and tried to escape from a tank 
when put into it. They leave their hiding-places towards dusk, becoming 
very lively, apparently less with the object of obtaining food (which they 
can only procure by quietly remaining in wait for it) than with that of 
enjoying themselves. The Australian tree-frog, which is endowed with a 
voice, indulges every evening in a musical performance. They become 
more quiet after midnight, and at sunrise they settle down in some resting- 
place, sometimes one individual selecting the same place for several con- 
secutive days. They prefer bluebottle-flies to every other insect, and 
never touch ants or black-beetles. They feed freely on meal-worms when 
other food is scarce ; but as they are frequently vomited, it is doubtful 
whether they could be kept in good health if restricted to this particular 
form of food. There is now in the gardens of the Zoological Society a 
collection of eight specimens of these Batrachia, which have been referred 
by Dr. Gunther to the genera Hyla and Telodryas, the latter being the 
best known form. The species are P. cceruleus (the Australian tree-frog), 
II. peronii, H. Jcrefftii , and H. phyllochroa. — Ibid. No. 75. 
