DISEASES OF PLANTS. 751 



author conducted a series of experiments on a bloclj of 1,000 trees divided 

 into two equal parts, one of which was sprayed with Bordeaux mixture while 

 the other was left uusprayed. 



At harvest all fruits were carefully examined and the results show con- 

 clusively that spraying cacao is an efficient method for controlling the diseases. 

 Allowing for labor, materials, etc., a gain of over $20 from 500 trees was 

 reported in a single season. 



Cacao canker, E. Essed (West Indian Bui, 12 (1012), \o. 3, pp. 302-308).— 

 The results of a six months' study of cacao canker in Surinam have led the 

 author to the belief that the disease is not primarily due to Phytophthora, as 

 has been claimed by Rorer (E. S. R., 23, p. 748), but is to be attributed to 

 attacks of Spicaria colorans, as previously described by A. E. van Hall de 

 Jonge (E. S. R.. 22, p. 547). 



A possible inference to be drawn from the studies on cacao canker, A. 

 Fredholm (West Indian BuL, 12 (1912), No. 3, pp. 30S-H10; Dcpt. Agr. Frini- 

 dad and Tobago But., 11 (1912), No. 70, pp. //6-//8).— The author is disposed 

 to criticize the claim of Rorer (E. S. R.. 23, p. 748) that pod ror. c.nnker. and 

 chupon wilt of cacao is solely due to Phytophthora sp. He considers canker as 

 a condition and not a specific disease and that several parasitic fungi at- 

 tacking cacao trees may produce cankerous conditions. 



Fungus diseases of cacao, F. W. South (West Indian Bui., 12 (1912). No. 

 3, pp. 277-302). — Popular descriptions are given of the principal diseases of 

 cacao known to occur in the West Indies and contiguous regions. A bibliog- 

 raphy of references is given. 



Bud rot of the coconut palm, J. B. Robeb (Dept. Agr. Trinidad and Tohago 

 Bui., 11 (1912), No. 70, pp. 68, 69). — The disease of the (oconut palm :ittributed 

 by Johnston (E. S. R., 26, p. t>49) to BaciUus coli is described. This disease ap- 

 pears to be quite prevalent in Trinidad, and sanitary measures have been taken 

 to prevent its spread, about 18,000 trees having been destroyed. Since this work 

 has been done there has been a marked reduction in new cases of infection, and 

 the author claims that this indicates rather conclusively that the disease can 

 be held in check by these measures, provided they are widely enforced. 



Rows of spots on the leaves of palmyra palms, W. INIcRak (Agr. Jour. 

 India, 7 (1912), No. 3, pp. 272-279, pis. 5). — The author describes a form of dis- 

 ease in the leaves of palmyra palm that is due to the fungus Pythimn palmivo- 

 rum, the cause of the bud rot of this tree. 



The parts of this palm most susceptible to attack are the succulent yellow 

 parts of the leaf sheaths. When the fungus begins its attack, well above the 

 level of the growing point, it eats its way inward through the leaf sheaths until 

 it reaches the young expanding leaves The tissues of the leaves are then 

 attacked, the fungus boring holes through them w'hich become quite evident 

 upou the expansion of the leaves. 



Cutting out the affected leaves is recommended as probably the most satis- 

 factory method of dealing with this trouble. 



A preliminary note on the heredity of fungus diseases of certain plants, 

 L. Blarinchem (Bill. 8oc. Bot. France, 59 (1912), No. 2-3, pp. 217-220).— A 

 record is given of observations on Lolium temulentum, which is often attacked 

 by a fungus; Althaa rosea; the seeds of which are commonly infected with 

 Puocinia mnlvacearum ; and (Enothera nanella, which is claimed to be a dwarf 

 form of CE. lamarelciana, attacked by a Micrococcus. From the frequency of 

 the occurrence of these diseases on their host plants, the author thinks the rela- 

 tion of symbiosis has lic-rome an acquired character. 



The case of Lolium temulentum and Althsea rosea, S. Bucket (Bui. Soc. 

 Bot. France, 59 (1912), No. 2-3, pp. 18S-191). — The author discusses the sup- 



