REVIEWS. 765 



inter-relations and influence upon forests. Most of the life histories, even, 

 that we find in the book are incomplete and will have to be confirmed and 

 amplified before they can serve any useful purpose. Some 480 Coleoptera 

 are enumerated as of forest importance. Of these some 56 have been 

 described by the author personally and five others bear his name. Of the 

 first number some will be found, we think, to have very little to do with 

 damage to forest growth either directly or indirectly as, for example, 

 H.ydrophilid<B, Silpliidce, and Tenebrionidie . 



On reading through the book somewhat hurriedly and with the further 

 disadvantage of not having existing notes to refer to at the moment, we 

 may mention various points that occur to us in connection with what is 

 written therein. Under '• Damage done to Roots " on page 12, Fhassus 

 malabaricus and other Hepialidai or Ghost-Moths have been omitted ; they 

 are well known root-borers and sometimes do much damage to Trema 

 orientalis in Bombay. Another species damages plants of the genus Stro- 

 bilanthes. It is more than probable both attack more important species as 

 well and their extraordinary fertility would point to their being enemies 

 to be feared where they occur. JDuomitus ceramicus also attacks fig trees of 

 many species (page 14). Under "Damage to Buds" it may be noted that 

 weevils bore into and breed in many of them. Under that to " Inflores- 

 cences " the damage done by butterfly larvfe of the lyceenid genera Virachola 

 and Rcqjcda which occur all over India might have been mentioned. The 

 imagines of the former lay their eggs on the flower and the larvse resulting 

 live in the fruit which they completely destroy ; the larvae of the latter eat 

 flowers. Both exist sometimes in large numbers. The statement advanced 

 tentatively at the bottom of page 31 about the generations of parasitic in- 

 sects has much support in fact. In many cases we know that the genera- 

 tions of host and parasite are equal in number and each of practically equal 

 duration. On page 40 the Arbela larva is mentioned, seemingly as some- 

 what exceptional in that it feeds on the bark of more trees than one. The 

 fact is not exceptional at all. There are very few larvas of Leindoptera that 

 are confined to one single foodplant and, we may therefore infer, few 

 coleopterous larvse either. Hundreds of instances could be adduced 

 proving this. In fact we imagine that it will be found eventually that the 

 number of insects that are confined to a single species for their food are 

 very few in number. 



This fact — that the foodplants of all insects may be varied — will be one of 

 the chief difliculties of preventing or combating attacks on forests by such 

 enemies ; and when we consider that there is hardly a forest in India 

 outside the pine and sal areas that do not contain dozens of species, all 

 mixed up together, of timber-trees, climbers and creepers and useless soft 

 woods that are as often as not closely related to each other, the diflaculties 

 can well be imagined by the most uninitiated. Take, for example, the case 

 of the teak-pest, Pyrhausta tnacliceralis, that occtirs sometimes in such 

 numbers as to skeletonize every leaf on every teak tree in tracts of 200 

 miles in length by 50 in breadth. It is called the Teak Defoliator. But 

 the larva — it is the larva that does the damage — feeds upon any member of the 

 botanical family Verbenacece and, may be, upon other plants as well ; it would, 

 therefore, be a very diflicult problem to devise any practical means to 

 combat or prevent attacks even in an isolated area, let alone in an extensive 

 teak forest. On page 50, this very insect is said to pupate on the ground 

 and, on the next page, we are told that the best way to destroy it is to 

 fire the forest ; the prescription may be all right for a small area where the 

 fire can be kept under absolute control and where conditions of the ground- 

 cover lend themselves to such control but, ordinarily, such a method would 

 be out of the question and its application over an extended area would 



