ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
41 
or before the Cretaceous era, and it spread over the whole continent. 
The next, the Euronotian, probably reached Tasmania from South 
America not later than the Miocene, and it probably drove out, par- 
ticularly on the east coast, many of the original inhabitants. Thirdly, a 
contingent of Papuan forms seized on the Queensland coast late in the 
Tertiary, and largely exterminated their predecessors. 
INVERTEBRATA. 
Lymphatic Glands of Invertebrates.* — M. A. Kowalevsky has pub- 
lished a preliminary notice of his experimental studies on these glands. 
He has made a considerable step by the introduction of bacteriological 
methods in order to demonstrate the phagocyte organs of Invertebrates. 
His first experiments were made on Pleurobranchus aurantiacus, into the 
body-cavity or under the subcutaneous tissue of which he introduced 
anthrax Bacilli, or B. tuberculosis avium. An hour after the injection 
the cells of the spleen of this Mollusc were more or less filled with the 
introduced Bacilli ; the animal did not appear to suffer at all, but a piece 
of spleen, taken four days after the injection, was cultivated in bouillon, 
and the injection of part of the cultivation killed a rabbit. Cultures 
made eight days after the injection gave rise to no colonies on gelatin 
or in bouillon, whence we may suppose that the Bacteria were killed. 
These experiments were repeated with Bhiline , Doris, and various 
species of Eolis ; in these last the Bacteria were absorbed by cells of 
the character of connective tissue arranged symmetrically on either 
side of the foot. 
While in Gastropods and Lamellibranchs solid substances injected 
into any part of the body are carried to the spleen or to the phagocyte 
cells which are scattered in the connective tissues, such injecta into 
Cephalopods remain at the spot where they are introduced. The 
phenomena exhibited by Cephalopods are detailed at some length, and 
evidence is brought forward to show that there is a kind of phagocyte 
gland in the gills themselves. 
Helix pomatia will support the introduction of large quantities of 
Bacteria without any inconvenience, and they become collected in the 
most delicate parts of the wall of the lung, which are essentially phago- 
cytic in function. 
A number of experiments have been made on Crustacea, but the 
results are as yet incomplete, but true glandular cells have been re- 
cognized ; the branchial glands of Decapods have been correctly described 
by Cuenot as phagocytes. 
In studying Arachnids Scorpions were first used ; the Bacteria were 
found to be absorbed by the spleen and the phagocytes of the fat-body. 
Epeira diadema and Lycosa Latreillei were found to die within two days 
ot the introduction of anthrax Bacilli. Scolopendra morsitans was almost 
exclusively studied as a representative of Myriopods ; Bacillus subtilis, 
prodigiosus, and anthracis were all found to be fatal in from two to five 
days ; the function of the spleen appears to be played by groups of cells 
disposed symmetrically in the body, surrounded by adipose tissue. Of 
* Bull Acad. Imp. St. Petersb., xxxvi. (1894) pp. 273-95. 
