239 
mammals; nor do they follow the external temperature at a level a few de- 
grees higher like those of reptiles. The temperature of Echidnas varies from 
25—30° C., and shows a diurnal variation of about 3°, the highest tempera- 
tures being in the afternoon. This variation is independent of alterations in 
- the external temperature. During the last few days several of the animals 
under observation had commenced hibernation, and their temperatures were 
now at the level of that of the air, but were following the alterations of this 
exactly. — Mr. G. H. Halligan exhibited, in quantity, examples of an un- 
determined Amphipod, which after rain, and with the wind in a certain di- 
rection, were to be found, regularly, strewn over the floor of the porch of 
his house at Hunter’s Hill. As his garden was kept in order, and there was 
nothing out of the ordinary in the way of cover for the animals, he was at a 
loss to know how they came to be so abundant; and he asked for an expla- 
nation of their occurrence. — On some Problems concerning the Develop- 
ment of Wingvenation of Odonata. By R. J. Tillyard, M.A., F.E.S. — 
As a result of a study of the tracheation of the developing wings of a very 
large number of dragonfly nymphs, the following problems have been elu- 
eidated. 1) The correct nomenclature for the veins in the cubito-anal area of 
the wing, and, in particular, the “anal loop” of Anisoptera. It is shown 
that the so-called “cubitus’’ is really the cubitus and analis fused a far as the 
first cubito-anal crossvein. Also the elongated ‘‘Italian” loop of the Libel- 
lulidae is, for the first time, correctly defined as lying between A» and Cuy, 
with a specially developed cubital supplement forming the midrib. 2) The 
oceurrence of a ‘‘bridgevein” in the Zygoptera is shown to occur not only 
in Lestes, as heretofore supposed, but also in Synlestes and Epiophlebia. 
These genera are therefore removed to form a new family Lestidae, and 
the formerly accepted relationship between Synlestes and Argiolestes is shown 
to be a cleverly masked case of convergence. 3) A beginning is made in the 
very difficult study of Zygopterid wingtracheation, and the complete four- 
branched anal trachea of the Anisoptera is shown to exist in Caliagrion. 
Hence it is claimed that the Zygoptera are undoubtedly reduced descend- 
ants of broader-winged dragonflies. 4) The primary cause of all the pe- 
culiarities in Odonate wing-venation is traced back to the change made by 
an originally land-dwelling larva to. fresh water, and the consequent deve- 
lopment of a flow of oxygen in the tracheal system from the anal end of the 
body. The wing-supply is shown to enter at the anal edge of the base, so 
that the costa and subcosta are in the most unfavourable positions, and de- 
velop but little, while the media competes with the radius for pride of place, 
and the cubitus and analis develop freely with a good oxygen-supply to 
draw upon. 
III. Personal-Notizen. 
Nachruf. 
Am 6. November starb in Hamburg Prof. Dr. Hermann Strebel, 
bekannt durch seine Arbeiten auf dem Gebiet der Mollusken und Tier- 
geographie. 
