302 



to its breeding places. During the summer of 1920 the author found 

 that Pissodcs spp. and Magdalis spp., when feeding, usually collect 

 near the places where they will oviposit later on ; in pine woods they 

 are found in numbers near winter-felled timber. It is probable that 

 Mydophilus pinipcrda, the life-history of which is very similar to that 

 of these beetles, behaves in a like manner. This would also explain a 

 concentration of crown injury independently of the occurrence or non- 

 occurrence of breeding facilities. 



The occurrence of .1/. pinipcrda is in close relation to modern methods 

 of thinning, which multiply breeding facilities. In forests that have not 

 been thinned the pest is much less abundant, and only weakened, 

 backward trees are infested and not even all of them. If such trees 

 are available after M. piniperda has swarmed, they are infested by 

 Pissodes pini and by Longicorns. In a forest where thinning has been 

 neglected, M. piniperda, P. pini and Longicorns are all found. Not 

 only weak trees but those broken by snow are infested ; the injuries 

 in both categories do not, however, result in much loss, though if 

 many such trees are present there is an increased number of beetles, 

 and these may prove a danger if thinning or felling is begun. 



The size of the felled trees influences the occurrence of .1/. pinipcrda. 

 Stems with a diameter of or under 3| cm. may be left Ij'ing without 

 risk and indeed with advantage because very few of the eggs (0-5 per 

 cent.) laid in them develop. Trees felled in summer and autumn 

 have undergone such changes by the spring as to be unattractive. 

 In exposed situations the changes are so rapid that clearing may be 

 continued up to November. In shaded places clearing must cease 

 by the end of August. It is possible that the non-dangerous period 

 may be extended b}' barking the trunks. 



Leonardi (G.). Monografia delle Cocciniglie Italiane. Opera postuma. 

 Edizione curata e accresciuta di un'Appendice dal Prof. F. Silvestri. 



[A Monograph on Italian Coccidae.l — Poriici, 1920, vii -j- 555 pp., 

 375 figs. [Received 25th April 1921 .] 



The author completed this important monograph just before his 

 death, from material collected during a lifetime's work on the Coccidae 

 of Italy. The volume is edited, by the author's wish, by Prof. 

 Silvestri. 



A general section describes the development and metamorphosis of 

 Coccids, their economic importance, natural enemies, and the measures 

 employed against them. A glossary of the terms used in the nomen- 

 clature of their external anatoni}' is included in this portion of the 

 work. 



The bulk of the volume is devoted to the description of 50 genera 

 and 147 species, much of the material having appeared before in the 

 form of scattered papers. ]\Iost of the numerous figures are original. 

 There is a key to the subfamilies, many specific keys, and full 

 references to the names adopted and to the synonymy. The author 

 has in some cases disregarded the commonly accepted rules of nomen- 

 clature, the subfamily name, He:micoccinak being used though there 

 is no genus Heinicoccus, and the only included genus being Kermo- 

 cocciis, a name that is substituted for Kcrmcs owing to its resemblance 

 to the Aphid genus, Chermcs. 



Much of the information available on the Coccidae of Europe is 

 contained in this volume, which will be of considerable assistance to 

 students of this group. 



