532 



and prevent injury from either excessive drought or heavy rains. 

 This enables the adults to remain for several weeks, or even months, 

 in the pupal chamber, waiting for rain to soften the ground sufticiently 

 for them to ascend to the surface. 



LE PoER Trench (A. D.). Report on Visit to Guatemala and Costa 

 Rica to investigate Methods of Cultivation of Coffee and its Diseases 

 and Pests. — Kenya Colony Dcpt. Agric, Xairobi, 1921, 19 pp., 

 18 figs. [Received 8th September 1921.] 



One of the most recent pests in Guatemala is the larva of a moth 

 that feeds on the shade tree Inga vera, causing, in some cases, almost 

 complete defoliation. Other pests recorded are scale-insects, against 

 which spraying is occasionally carried out, thrips, cut-worms, a leaf- 

 mining moth, mealy bugs and an Aphid. On the whole little injury 

 is caused to coffee by diseases and pests in Central America, and not 

 much spraying is done to control them. 



Blatchley (W. S.) & Leng (C. W.). Rhynehophora or Weevils of 

 North Eastern America. — Indianapolis, The Nature Publishing 

 Co., 1916, 682 pp.. 155 figs. [Received September 1921.] 



The geographical scope of this work covers the United States and 

 Canada east of the Mississippi River. Its object is to furnish a manual 

 that will enable the student to classify and identify weevils, and to 

 this end many matters relating to synonymy and other more strictly 

 technical questions have been omitted. Keys to the families, genera, 

 species and other subdivisions form an important part of the work. 



Following the description of each species are notes on its distribution, 

 food habits, etc., and in the case of species of economic importance, 

 a summarised life-history is also given, with notes on the damage done. 



The volume concludes with a complete bibliography, and a plant and 

 generic index, as well as one covering the new genera and species 

 described. 



Ralfs (E. M.). An Abstract of the Legislation in Force in the British 

 Empire dealing with Plant Pests and Diseases up to the Year 1920. — 



London, Imp. Bur. Ent., 1921, <do pp. Price 2s. Qd. 



This summary, which is arranged geographically, contains in a 

 compact form the legislation enforced with regard to plant pests and 

 diseases up to the year 1920, with an index to the pests, plants and 

 places dealt with. 



Summary of Laws and Regulations in Force in Ceylon in respect of 

 Plant Pests and Diseases. — Cevlon Dept. Agric, Peradeniya, 

 Bull. 48, May 1921, 6 p]x [Received 6th September 1921.] 



The legislation in Ceylon summarised in this paper dates from the 

 year 1901. That of recent years has previously been noticed [R. A.E., 

 iv, 484 ; v, 46, 232, 480 ; vi, 87]. 



Havil.wd (M. D.). The Experimental Production of Winged Forms 



in an Aphid, Myzus ribis, Linn. — Ann. A pp. Biol., Cambridge, 

 viii, no. 2, August 1921, pp. 101-104. 



Most Aj^hids are dimorphic in respect of the viviparous partheno- 

 genetic generations, which may be either winged or wingless, but 

 the factors determining the appearance of either form are not yet 



