52 EXPEEIMENT STATION RECORD. 



an additional 16 per cent of vegetable matter which could not be definitely 

 determined as almond meats. The animal food, amounting to 15 per cent, 

 was made up of beetles and ants. 



Mention is made of the California blue jay as being by far the worst pest of 

 the almond orchard. 



The economic value of the western meadow lark in California, H. C. 

 BRYAivr {California Sta. Bui. 236, pp. 16, figs. 7). — A report based upon the 

 investigations previously noted from other sources (E. S. R., 28, pp. 155, 351). 



The instinct of insects, J. H. Fabre (Les Merveilles de V Instinct chez les 

 Insectes. Paris, 1913, pp. 265, pis. 16, fig. 1). — A popular account. 



The poison exponent: A symbol of the toxicity of chemicals in their 

 relation to insects, T. E. Holloway (Jour. Econ. Ent., 5 (1912), No. 6, pp. 

 Jf52-Ji56) .—The author's studies have led him to formulate the following law: 



" If the length of life of a poisoned insect may be taken to indicate the tofic 

 value of the chemical to which that insect is subjected, then the toxic values 

 of two chemicals vary inversely with the lengths of life of two insects respec- 

 tively subjected to them, assuming that the insects are of the same species and 

 at the same period of their life cycle, and that environmental conditions are 

 equal." 



[Report of the] division of entomology, Z. P. Metcalf (North Carolina 

 Sta. Rpt. 1912, pp. 31-33). — Work with the grass billbug (Sphenophorus par- 

 vulus) indicates that a partial second generation usually occurs in the vicinity 

 of West Raleigh. Notes are also presented on other pests of the year. 



Report of the entomologist, D. L. Van Dine (Porto Rico Sugar Prodticers' 

 Sta. Rpt. 1912, pp. 15-22). — A brief report of the work of the year with insect 

 enemies of sugar cane, including accounts of their occurrence and injury. 



During the year the West Indian sugar-cane leafhopper (Delphax sacchari- 

 vora) was discovered breeding on cane in Porto Rico. Observations made of its 

 life history show the eggs to be deposited in or along the midrib of the leaf, 

 being usually inserted from the underside of the leaf. Several eggs, vary- 

 ing In number from 3 to 11, are inserted in a single chamber and occur 

 in a row on end at right angles to the long axis of the leaf. After the eggs 

 are inserted therein, the opening of the egg chamber is covered by a white, 

 cottony, wax-like secretion, the egg clusters being easily located by this 

 conspicuous white covering. The young and adult leafhoppers occur upon the 

 cane leaves and feed upon the juice of the plant. The injury to the plant 

 consists not only in their absorption of the juice, but in the rupture of the 

 tissues of the plant by their punctures, allowing excessive evaporation and the 

 entrance of pathogenic fungi. An egg parasite belonging to the family Myma- 

 ridse was bred in some numbers. 



A brief account is given of work with the sugar-cane borer (Diatrcea sac- 

 charalis), a circular relating to which has been previously noted (E. S. R., 27, 

 p. 659). A tachinid of the genus Hypostena, probably new to science, is said 

 to have been reared from its tunnel in the cane. 



The fungus parasite Cordyceps harheri is found infesting the larva of the 

 moth-borer In all of the districts on the island but in no great amount in any 

 locality. The parasitic fungus Metarrhizium. anisoplice, introduced from Hawaii, 

 has been found to attack both the larva and adult of the May beetle (Lachnos- 

 terna sp.) in the experimental cages. Mention is made of the discovery of 

 a tachinid parasite of the May beetle, a description of which by W. R. Walton 

 under the name Cryptomeigenia aurifacies has been previously noted (E. S. R., 

 28, p. 657). The other insects discussed are the mole cricket, or " La Changa " 

 (Scateriscus didactylus), sugar-cane mealy bug (Pseudococcus sacchari), the 

 weevil stalk borer (Metamasius hemipterus), which has been found to be at- 



