Visual display of the Aldo Leopold papers : 9/25/10-4 : Species and Subjects

				
dures a higher temperature than many associated herbs and trees. The 
relation of thickness and density of the testa and inherent characteristics

of the species appear to account in part for the differences in temperature

endurance. 
3. A New Concept of Forest and Some Ecological Implications. (30 
min.) (Lantern.) W. C. Lowdermilk, California Forest Experiment Station,

Berkeley, California. 
A series of experiments at Berkeley, California, have indicated that 
forest litter functions far beyond its saturation by rain water in influencing

the absorption of precipitation by soil profiles. Destruction of litter by

burning or otherwise baring soils, increases surficial run-off from sloping

lands; reduces soil supplies of absorbed moisture and sets in motion ac-

celerated erosion in excess of geologic norms responsive to climate, vegeta-

tion, topography, soil development and time. 
4. Parasitism of the California Valley Quail by Haemoproteus Lophor- 
tyx. (15 min.) (Lantern.) E. C. O'Roke, Division of Fish and Game. 
The finding of a blood parasite of the genus Haemoproteus in the Call- 
 
fornia Valley Quail at Yountville, California, in December, 1927, yielded

the first record of parasitism by this type of protozoan in a bird belonging

to the genus Lophortyx. Extensive studies carried out since that time show

that the parasite is widely distributed among all of the species and sub-

species of the genus Lophortyx in California. The parasite is new to science

and has been described as Haemoproteus lophortyx., Forty-five per cent 
of the quail are infected. It is transmitted from quail to quail by the para-

sitic louse fly Lynchia hirsuta Ferris. It has a complicated life cycle simi-

lar to that of the malaria parasites of man. The sexual cycle has been 
worked out in detail and an important contribution made to the knowledge

of gametogenesis in a sporozoan of this type. 
 
"of Statistical Studies of Marine Phytoplankton at the 
Scripps Institution of Oceanography. (15 min.) Winfred Emory Allen, 
Scripps InsItution. 
These studies have been made on material collected along the East 
coast of the Pacific Ocean from Callao, Peru to Dutch Harbor in the Aleut-

ian Islands, and along steamer routes from San Francisco to Hawaii, to 
Australia and New Zealand, but mostly off the coasts of California. Special

methods and equipment (including the Allen closing bucket) have been de-

vised to meet the obligatory conditions of collecting. The total number of

collections is nearly twenty thousand, all made by filtering a measured 
amount of sea water through No. 25 bolting silk (mesh openings between 
fifty and one hundred micra in diameter.) About eighteen thousand catches

have been made from the surface level and over one thousand from levels 
 
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