98 
POPULAR SCIENCE REVIEW. 
coloured flowers. Mr. Miiller gives the following account of it : — J. Mac- 
douall Stuart, the famous explorer, brought the first specimens from Attack 
Creek, south of Arnhem’s Land. It is to be feared that the plant has a wide 
range in tropical Australia (though it was not met with on the route of the 
expedition to which I was attached). To some extent the occupants of terri- 
tory in which it occurs may, however, guard against this bane, since the plant 
has become widely known ; nor is it unlikely that it may be extirpated by 
setting fire repeatedly to the scrubby ridges on which it grows. G. grandi- 
Jlorum is the only species of the genus as yet found beyond South-West 
Australia, where several congeners (G. bilobum, G. calycinum, G. callistachys , 
G. oxylobioides ), on account of their poisonous properties, render extensive 
tracts unoccupiable. On a future occasion I shall have to enter on detailed 
statements of the effects of the Gastrolobia oil the animal frame, give the 
results of their chemical analysis, and refer to the highly deleterious effect of 
the Swainsonia Greyana (which, as a pasture herb on the Darling flats, fre- 
quently causes the death of horses during dry seasons, when other herbage 
fails), as well as to the deadly effect of the Lotus australis on sheep. 
The Pollen Grains of Ranunculus. — Professor Gulliver gives the following 
as the results of his measurements and observations of the pollen grains of 
Ranunculus : — R. auricomus, pollen grains round and smooth, and of an 
inch in diameter ; R. acris , pollen grains round and smooth, and of an 
inch in diameter ; R. repens, round and smooth, and shs- of an inch in dia- 
meter ; R. bulbosus, round and smooth, and y-Jy of an inch in diameter ; 
R. hirsutus, pollen grains smoothish, with three depressed scars, and -g^-g of 
an inch in diameter ; R. arvensis , pollen grains round, rough, and so much 
larger than those of the other species as to measure -y-f-o- of an inch in 
diameter. The roughness remains when the pollen grains are heated either 
with dilute acids or water. — Yide Microscopical Journal, No. XX. 
The Process of Fructification in the Sphcerice. — Herr Sollman thus de- 
scribes one of the processes of fructification in this low order of plants : — 
Eight membraneless bodies (cytoblasts) are developed in the ascus, either 
by free cell formation, or by division, but probably by the former. These 
bodies have a smooth surface, and become elongated in the direction of the 
longitudinal axis of the ascus. Thus they become first roundly elliptical, 
and at last elongate-elliptical. Up to this time they have no spiral mem- 
brane. At this stage the spermatia attach themselves by one end firmly to 
the surface of the cytoblasts. At the point where the spermatium attaches 
itself, the surface of the young spore gradually disappears, and the pole of 
the spermatium thus at last comes into contact with the contents of the 
spore. The spermatia come from all directions, and attach themselves firmly 
all over the surface of the young spore. The portion of the spermatium which 
penetrates the spore remains visible within it for a considerable time. Ulti- 
mately, the spermatia make their way into the spore, and the edges of the 
openings through which they have entered unite, leaving the surface of the 
spore with slight elevations at the points of entry. As the spermatia get 
deeper into the spore, these elevations disappear, and the surface becomes 
even. The spore is now for the first time surrounded by a double-outlined 
membrane. By degrees the spermatia become disintegrated, and are no longer 
visible in the contents of the spore. 
