January-, 1920] PATIIOLOCY 17 



11"). SCBOBVEBS, T. A. C. Vreemde lichaampjes in zieke spinaziewortels. |Unknown 

 corpuscles in diseased spinach roots.] Meded. I/indbouwhoogeschool Wageningen 15:7.")- 

 (84). PI. 10. 191S. — English resume" on p. 83. — The main roots of diseased plants are some- 

 what shriveled and black; the smaller rootlets are similarly affected or are absent. Cells of 

 root parenchyma are filled with small, (15 x 5ft), somewhat spindh-.-diaped bodies. The bo 

 have the power of movement but tlii^ was seldom observed. Attempts to cultivate them 

 were unsuccessful as were infection experiments. "Although it is by no means proved, the 

 author is inclined to think, that these newly discovered X-organisms, as he proposes to call 

 them for the present, are a form of not yet described protozoa." — D. Reddick. 



116. Smith, Ralph E., E. O. Essig, and Geo. P. Gray. Handbook of plant disease and 

 pest control. California Agric Exp. Sta. Circ. 204. 86 p. 1918. 



117. Spixks, G. T. Damping-off and collar rot of tomatoes. Ann. Rept. Agric. Hortic. 

 Res. Sta. Univ. Bristol 1917:25-27. [1918]. — Damping-off occurs in seedlings and collar rot 

 in plants up to a foot in height. The cause of the trouble is an undetermined species of Phy- 

 tophthora. The fungus persists for a long time in soil but in what condition is not known. — 



D. Reddick. 



118. Stewart, Albax. A consideration of certain pathologic conditions in Ambrosia tri- 

 fida. Amer. Jour. Bot. 6: 34-46. PI. 2, fig. 1. 1919. — The author first describes the normal 

 internal structure of the stem of this species, and then the modifications in structure caused by 

 attacks of Protomyses andinus Lagh., of the stem borer, Papaipema nitela Gn., of both the 

 fungus and the insect together, and by mechanical wounds. There is little misplacement of 

 xylem cells in the galls formed by the parasites. Increase in parenchyma at the expense of 

 the xylem, broadening of the rays, and reduction in number and size of vessels, are more 

 marked in the Protomyces gall than in that of the insect. Mechanically wounded tissue is 

 characterized by radical misplacement of the cells, vertical shortening of the rays, increase 

 in parenchyma and reduction in number of vessels. Where both insect and fungus have acted 

 together, the resulting tissue is characteristic of the fungus gall, the stimulus from the insect 

 being inactive. The stimulus from the insect, though weaker, is able to exert an influence 

 much farther away from the source of the stimulus than is the stimulus from the fungus. — 



E. W. Sinnott. 



119. Trevor, C. G. A fungus attack on the deodar. Indian Forester 44: 130-131. 1918. 

 — Referring to article by Glover, Indian Forester 43 : Dec. 1917, author states that the plants 

 shown in the illustration "exhibit all the symptoms of plants suffering from insufficient light." 

 — D. Reddick. 



120. Trotter, A. La "rabbia" o "antracnosi" del cece ed il suo produttore. [Rabbia or 

 anthracnose of chick-pea and its cause.] Rev. Patol. Veg. 9: 105-114. 1918. — See Bot. 

 Absts. 3, Entry 376. 



121. Venkatarama, Ayyar, K. R. Is spike disease of sandal (Santalum album) due to 

 an unbalanced circulation of sap? Indian For. 44: 316-324. PI. 19. 1918.— A criticism, with 

 supporting evidence, of: Hole, R. S. Indian For. 43: 430-131. 1917. [See Bot, Absts. 2, En- 

 tries, 1297, 1298.]— Seven sandal trees were isolated from any host by deep encircling trenches 

 and by keeping free from vegetation the soil within the trenches. One tree has remained 

 healthy for 24 months and 6 trees for 18 months.— Roots were severed, haustoria cut off and 

 sulfuric acid injected in roots to simulate damage done by fire. At the end of 15 months the 

 wounds were largely healed, and the trees healthy. — On two occasions heat from burning brush 

 killed or injured several sandal trees but those not too badly damaged put out healthy foliage. 

 — Clearing out all trees except sandal in a large area gave a sudden change of "conditions nec- 

 essary for an unbalanced circulation of sap" but the spike disease did not appear. — Experi- 

 ments in girdling never have been accompanied or followed by spike disease. — The conclusion 

 is reached that unbalanced circulation of sap is not the cause of spike disease. [See also Bot. 

 Absts. 2, Entries 1177, 1297, 1303, 1304; 3, Entry 104.]— D. Reddick. 



BOTANICAL ABSTRACTS, VOL. Ill, NO. 1 



