272 



RiVEROS (E.). Citrus cultivados en el Chaco. [Citrus Culture in the 

 Chaco Region.] — Bol. Minist. Agric, Buenos Aires, xxiii, no. 1, 

 January-December 1918, pp. 156-160. [Received 30th April 

 1919.] 



The cultivation of citrus in the Chaco district is not affected by 

 many insect pests. Two species of scale-insects occur throughout 

 the citrus plantations, the commonest being Lepidosajjhes heckii 

 {Mytilaspis citricola) ; these, however, do not cause serious damage 

 and measures against them are very seldom adopted, though it is 

 possible that they may develop into a serious menace to the industry. 



Saalas (U.). Die Fichtenkafer Finnlands. Studien uber die 

 Entwieklungsstadien, Lebensweise und geographisclie Verbreitung 

 der an Picea excelsa, Link., lebenden Coleopteren nebst einer 

 Larvenbestimmungstabelle. [The Spruce Beetles of Finland. 

 Studies on the Developmental Stages, Life-History and Distribu- 

 tion of the Coleoptera living on Picea excelsa^ Link. , with a Key to 

 the Larvae. J — Annates Acadetniae Scientiarmn Fennicae, Helsing- 

 fors, Ser. A, viii, no. 1, 1917, 547 pp., 9 plates, 1 map. 



The Coleopterous fauna of Finland has been relatively well worked 

 from a systematic point of view, though biological data are almost 

 entirely lacking. In this volume, which is the outcome of investiga- 

 tions carried on from 1912 to 1915, the term " spruce beetle " is 

 used in a wide sense, and includes such species as only occasionally 

 occur on Picea excelsa. On the other hand those beetles are excluded 

 that are not truly arboreal, but shelter beneath the spruce bark 

 more or less by chance. For instance, Pyrochroa pectinicornis, a 

 typical birch insect, has been included because the larvae that w^ere 

 examined had apparently spent the entire larval stage under the 

 spruce bark, whereas certain Chrysomelid, Curculionid and other 

 beetles that are found under the bark, especially in autumn and 

 spring, have been omitted because their true halDitat is elsewhere. 

 The exceptions to this last rule are justified in the second part of this 

 volume, in which, under an arrangement according to families, the 

 species are dealt with singly, many details of the life-history, distribu- 

 tion and habitat being recorded in each case. 



The first part, covering 276 pages, deals generally with these 

 beetles, their economic importance, distribution, food and occurrence 

 on various parts of the spruce, and contains many tables. In a 

 number of cases the existing literature does not afford adequate 

 means for identification and in many of them the adult had to be 

 bred out. The key at the end of this work is intended to enable 

 the larvae of all the species known to the author to be identified. 

 Of those that he is unacquainted with only a few are included owing 

 to the difficulty in finding satisfactory characters for comparison. 

 The number of species fully dealt is 341 of w^hich 289 were actually 

 observed to occur in more or less abundance on spruce. This last 

 figure represents 9*9 per cent, of the 2,927 species of Coleoptera 

 recorded in Finland up to 1900 according to the " Catalogus Coleop- 

 terorum Faunae Fennicae " of J. Sahlberg, the author's father. 



