June, 1920] ECOLOGY 285 



1959. Gray, John, and George J. Peibcb. The influence of light upon the action of 

 stomata and its relation to the transpiration of certain grains. Amer, .Jour. Bot. 6: 131 \~>~>. 

 18 fig. 1919.— See Bot. Absts. :i, Entry 436. 



1960. Griggs, Robert F. Asclepiadora viridis in Ohio. Ohio. Jour. Sci. 19: 299. 1919. 

 — The occurrence of Asclepiadora viridis in the Sugar Grove area is a notable extension of 

 the range of this southern plant. — //. 1). Hooker, Jr. 



1961. Griggs, R. F. Scientific results of the Katmai expeditions of the National Geo- 

 graphic Society. IV. The character of the eruption as indicated by its effects on nearby vege- 

 tation. Ohio Jour. Sci. 19: 173-209. 1919. The eruption of Katmai in 1912 destroyed the 

 surrounding vegetation by acid rains, ashfall, hot blasts, mud flows and fires. All life was 

 annihilated over an area of 140 square miles. The condition and reactions are described and 

 illustrated by photographs. Plants that lay buried for 3 years came up from the old roots 

 in 1915, when the ash was removed by a flood. The cause of dormancy is discussed. [See 

 also next following Entry, 1962.]— Hem -y D. Hooker, Jr. 



1962. Griggs, Robert F. Scientific results of the Katmai expeditions of the National 

 Geographic Society. IX. The beginnings of revegetation in Katmai Valley. Ohio Jour. Sci. 

 19: 318-342. 1919. — The first stages of revegetation in the valley of Katmai River are de- 

 scribed. The agents of revegetation are: (a) surviving woody plants, chiefly the larger 

 willows, that protrude through the ash; (b) herbage in places cleared of ash, consisting of 

 Elymus arenarius and Equisetum arvense; and (c) seedlings of lupines, willows and the grasses, 

 Deschampsia caespilosa and Calamagrostis langsdorfii. The more important factors deter- 

 mining distribution seem to be the concentration of requisite salts, high wind velocity and 

 shifting streams. The essential problem of revegetation is the nitrogen supply. [See also 

 next preceding Entry, 1961.] — H. D. Hooker, Jr. 



1963. Gruber, C. L. Fragrant wildflowers. Amer. Bot. 25: 8-13. 1919.— A list of 125 

 fragrant species from Pennsylvania is given and an attempt is made to indicate the amount of 

 fragrance of each. — W. N. Clute. 



1964. Harshberger, J. W. Alpine fell-fields of eastern North America. Geog. Rev. 7: 

 233-255. 12 fig. Apr., 1919. — The fell-fields (a European term for rocky areas with sparse 

 vegetation in cold climates) described and illustrated are on the higher mountains of New 

 England and New York. Comparisons are made with similar areas in other parts of the world. 

 The author believes it is important to correlate in similar fashion the related plant formations 

 of different regions. — Roland M. Harper. 



1965. Hitchcock, A. S. A botanical trip to Mexico. Sci. Monthly 8: 129-145, 216-238. 

 S4fig., 5 maps. 1919. — The article is illustrated with views of Mexican scenery, life and plants. 

 It is a brief summary of observations made in connection with a trip in the summer of 1910. 

 The technical report upon the grasses is published as Contr. U. S. Nat. Herb. 17: 181-1S9. 

 1913. A small map with 500-meter contour interval indicates the greater topographic features, 

 a plateau 3000-8000 feet in altitude with a strip of lowland along each coast. Other maps 

 give the annual and monthly rainfall. — Northern Mexico is arid, the rainfall being less than 

 10 inches (25 mm.). The precipitation increases towards the south. The maximum, 114 

 inches (2867 mm.), is at Cordoba. — A map giving the location of the 37 collections, shows 

 them to be widely distributed, with the larger number of places in the region from Cordoba 

 to Mexico City. A few places are south of this area and many are north, extending almost 

 as far as El Paso, Texas. A table is given listing the collections by locality, state, altitude, 

 date, and field numbers of the specimens. — The second part of the paper discusses the com- 

 mon wild grasses of Mexico. It is suggested that the ecologist will readily coordinate the 

 flora upon the basis of the grasses. Thirteen species are listed for the eastern coastal plain 

 and six for the western. These coastal plains grasses are of no particular agricultural impor- 

 tance, except those on the sandy flats around Vera Cruz. The plateau furnished a much larger 



