30 PROCEEDINGS OF THE CALIFORNIA 
of ocean currents and the pressure of the greater masses from the northward; 
or as part of the great ice sheet that covered the continent and moved slowly 
southward. 
As a glacial mass it extended seaward many miles, as indicated by its action 
upon the islands which I therein named. And it seems not only possible, 
but highly probable, that this great ice sheet not only covered and bordered 
the continent, but that it projected far into the oceans; and not improbably 
may have occupied a large part thereof ! 
We know its effect in the terracing of the rocky coast of Northwest America; 
and in cutting the channels through the Santa Barbara Islands; and still 
further, I believe we see other effects of its existence and extent in the present 
nearly ice-cold temperature of the great depths of the ocean! 
The theory which attempts to account for that low temperature by the 
transfer of Arctic waters to the depths of ocean utterly fails in the case 
of the Northern Pacific Ocean, where the narrow contracted throat of Behring 
Strait not only could not give egress to such a volume of cold water in millions 
of years, but is actually the channel for the passage of the Kamschatka branch 
of the Japan warm stream into the Arctic basin. A small thread of the Arctic 
waters does pass through Behring Strait, but it is of very limited section, for 
the strait itself has a section of only thirty miles in width by twenty-five 
fathoms in depth. 
The more that I have looked at the discussions of the theory of the inter- 
charging heated surface waters of the equatorial regions with the cold waters 
of the Arctic basin, the more strongly I am convinced of its weakness and 
insufficiency. And in searching for the cause of the nearly ice cold waters 
of the ocean depths, the proved former existence of the great ocean coast 
ice belt, and probably of ice masses occupying the high northern and south- 
ern areas of the oceans, have seemed to me sufficient to account for the low 
temperatures which deep sea explorations have proven to exist. 
Dr. Kellogg read a paper describing the different varieties of 
Kucalyptus, with their characteristics. 
Different Varieties of Eucalyptus, and their Char- 
acteristics. 
(Letter to Mr. Ellwood Cooper, of Santa Barbara.) 
BY DR. A. KELLOGG. 
According to promise, I collate a few brief notes on Hucalypti.* As you 
have Dr. Mueller’s work I need not quote from it, but give such information 
as can be obtained from other sources. For the medical properties of extracts, 
etc., I refer you to the Doctor. 
I wish to say, first, that I know of but two trees (which now occur to me) 
that are perfectly proof against the Teredo navalis, or pile-borer of tide water, 
* There are one hundred and thirty-five species. A long time may elapse before a thorough 
knowledge of these and their numerous varieties are fully known. 
