246 
PROGRESS OF MICROSCOPICAL SCIENCE. 
long. 71° 36' E., a little to the north of the Heard Islands, the tow-net, 
dragging a few fathoms below the surface, came up nearly filled with a 
pale yellow gelatinous mass. This was found to consist entirely of 
diatoms of the same species as that found at the bottom. By far the 
most abundant was the little bundle of silicious rods (pi. iii. fig. 5) 
fastened together loosely at one end, separating from one another at the 
other end, and the whole bundle loosely twisted into a spindle. The 
rods are hollow, and contain the characteristic endochrome of the Dia- 
tomaceoe. Like the “ Globigerina- ooze,” then, which it succeeds to the 
southward in a band apparently of no great width, the materials of 
this silicious deposit are derived entirely from the surface and inter- 
mediate depths. It is somewhat singular that diatoms did not appear 
to be in such large numbers on the surface over the Diatom-ooze as 
they were a little farther north. This may perhaps be accounted for 
by our not having struck their belt of depth with the tow-net ; or it 
is possible that when we found it, on the 11th of February, the 
bottom deposit was really shifted a little to the south by the warm 
current, the excessively fine flocculent debris of the diatoms taking a 
certain time to sink. The belt of Diatom-ooze is certainly a little 
farther to the southward in long. 80° E. in the path of the reflux of 
the Agulhas current, than in long. 108° E. 
Structure of the Lobules of the Liver. — Herr G. Asp gives a 
valuable paper of some length on this subject in Ludwig’s ‘ Arbeiten ’ 
(vol. viii.), which has been lately fully abstracted in the ‘ Medical 
Record.’ We merely give the following paragraph. He says, the 
bile-ducts, in penetrating into the lobule, lose at the same time their 
cylindrical epithelium and their striated investment, their walls 
being composed only of fusiform nucleated plates disposed in spirals. 
E. H. Weber has already shown that a solution of alkannine in tur- 
pentine penetrates into the interior of the cells, and the author has 
satisfied himself by the injections of gutta-percha dissolved in 
alcohol, and afterwards by the non-passage of a watery solution of 
Berlin blue into the cells, that there is no rupture of the cells pro- 
duced by the injection, and that therefore this passage of alkannine 
and gutta-percha into these cells must take place by filtration. 
MacGillavry, as is known, injected intralobular perivascular spaces, 
both by injection of the lymphatics in the liver of a dog, and also by 
the “ puncture ” ( Einstich ) method. Frey and Irminger confirmed the 
existence of these spaces in the liver of the rabbit. E. Hering, 
however, denied that these spaces were the origin of the lymphatics, 
and did not succeed in injecting them in the liver of the rabbit. Asp 
has succeeded in injecting them in the rabbit, by forcing serum 
for a long time into the vena port®, under a pressure of 30 to 50 
millimeters of mercury (1-2 to 2 inches). 
Is Peronospora the cause of the American Onion Blight 1 — According 
to the editor of ‘ Grevillea ’ (March), this seems to be doubtful. He 
says, the cause is supposed to be a species of Peronospora, but the 
rough figures [given] forbid any such conclusion. It is much more like 
a species of Fusisporium. There would appear from the description 
